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The growth of the world population has led to an increase in the demand for fresh water. Water pollution is often caused by hasty urbanization without proper management of hazardous waste. Therefore, it is vital to implement new methods to remove pollutants from water. In the current study, an antimicrobial nanocomposite adsorbent composed of Arabic gum- grafted -poly(para phenylene diamine) (AG-g-PpPA) decorated with metal-organic framework and copper nanoparticles (AG-g-PpPA@MOF(Fe)/Cu) was synthesized via in-situ copolymerization. The nanocomposite was utilized for eliminating the antibiotic cloxacillin from water solutions. The effects of different factors were analyzed, including pH, the quantity of adsorbent, contact time, and preliminary cloxacillin concentrations. Ideal parameters were pH 7, 5 mg adsorbent dosage, 10 min contact time, and an initial 500 mg/L cloxacillin concentration. The adsorption process followed the Freundlich isotherm equation, with a maximum adsorption ability of 400 mg/g. The kinetics information appropriately fits a pseudo-second-order model. Thermodynamic calculation showed the adsorption occurred spontaneously. The nanocomposite also displayed antibacterial action in contradiction to Escherichia coli and Staphylococcus aureus. Additionally, the adsorbent could be recovered and reused effectively. The excellent adsorption ability highlights the potential of AG-g-PpPA@MOF(Fe)/Cu adsorbent for eliminating pharmaceutical pollutants from wastewater. [Display omitted] [ABSTRACT FROM AUTHOR]

Tröger's-based polymeric membranes have received tremendous attention for their inherent high free volume and excellent gas permeability. However, its selectivity was still unable to meet their industrial demand. In effort to achieve an optimization comprehensive performance, a set of homogeneous polymer chains was synthesized to fine-tune the free volume. These membranes were designed by copolymerization diamine moiety of 3, 3′-dimethylbiphenyl-4, 4′-diamine and 2, 2-bis [4-(4-aminophenoxy)phenyl] hexafluoropropane. Significant characterizations of their physical properties and chemical structures were carried out by FTIR, TGA, XRD, and mechanical strength. The effects of variation diamine content ratio were studied. An available simulation was carried out to elucidate the influence of introduced diamine. The permselectivity of membranes was evaluated by H 2 , CO 2 , O 2 , N 2 , and CH 4. The objective performances of feed gas pressure, test temperature, and aging stability on membranes were further studied. The exciting results demonstrated that our membranes exhibit improved gas performance. Notably, for H 2 separation, the H 2 /N 2 and H 2 /CH 4 selectivity was significantly enhanced by 125.7% (from 27.20 to 61.40) and 126.9% (from 30.41 to 69.02) with the addition of 30 mol% fluorinated diamine moiety while without much-compromising gas permeability was observed. These findings enlighten a facile and effective strategy in Tröger's-based polymer design towards high-purity gas separation. • Composite Tröger's-based polymeric membrane was prepared for gas separation. • Fluorinated aryl ether moiety diamine was used to tuning the free volume of membranes. • The H 2 /N 2 and H 2 /CH 4 selectivity was enhanced by 125.7 % and 126.9 % with the addition of 30 mol% diamine. • The attracted H 2 /CH 4 performance was very approached to the 2008 Robeson's upper bound. [ABSTRACT FROM AUTHOR]

[Display omitted] Palladium complexes with inexpensive and available vicinal diamines can serve as catalysts for the reductive Heck-type cyclization. o -Bromo- N -(2-phenylallyl)anilides are converted into the corresponding 3-methyl-3-phenylindolines, the analogous cyclization occurred for 2-bromo-4-methylphenyl 2-phenylallyl ether and N -(2-bromophenyl)-2-phenylacrylamides. The use of (1 R ,2 R)- N , N' -dibenzylcyclohexane-1,2-diamine provides up to 35% ee of the indolines; this is the first case of asymmetric induction during the reductive Heck reaction involving diamine complexes. [ABSTRACT FROM AUTHOR]

[Display omitted] Structurally analogous C- and N-linked 1,4-bis(imino)-functionalized benzenes react with acetylenes in the KOBut/ DMSO superbase system to give the corresponding bis-(propargylamino)-containing derivatives in 62–82% yields (C-linking) or 38–42% yields (N-linking). In the latter case, with phenylacetylene, the yields of mono- and bisadducts were 32 and 38%, respectively. The observed dissimilarities between both bisimine chemotypes in the reactivity and synthetic outcomes imply the long-range adverse repulsive interaction between nitrogen anionic center and the second nitrogen atom in the N-linked 1,4-bis(imino) benzenes. [ABSTRACT FROM AUTHOR]

The graphene oxide-poly (p -phenylene diamine) (GP) composite is synthesized through in-situ polymerization of p -phenylene diamine on GO sheets and used as an efficient support material for electrodeposition of Ni and Mn. The resulting GP/Ni–Mn catalyst shows high catalytic activity, stability and durability for methanol electrooxidation. The surface area of GP composite is calculated to be about 28% and 36% higher than GO and PpPDA, respectively. In addition, combining Ni and Mn demonstrated some synergetic effect for methanol electrooxidation. The electrochemical active surface area of GP/Ni–Mn is about 1.625 cm2, which is much higher than GP/Ni and GP/Mn. GP/Ni–Mn nanocomposite presented 87.3% of the peak current after 5 h and almost 83.16% of the maximum current for 500 cycles. The excellent characteristics of this composite are attributed to high surface area, high electrochemical active surface area and fine distribution of metallic particles on the support material. • GO-PpPDA was synthesized via in-situ polymerization of pPDA and used to modify CPE. • Ni and Mn particles were deposited on the surface of modified CPE by chronoamperometry. • The electrochemical properties of different support materials were studied. • The nanocomposites used for electrooxidation of methanol in alkaline media. • The results showed the best performance of GO-PpPDA/Ni–Mn nanocomposite. [ABSTRACT FROM AUTHOR]

A highly fluorescent zinc probe of reduced Schiff base (rBDZn) has been identified as promising chemosensor towards cadmium ion sensing supported by theoretical and experimental approaches, where rBDZn captures Cd2+ and crystallize out from the system. [Display omitted] • A zinc-based fluorescent probe (rBDZn) having reduced Schiff base backbone with N,O-donor atoms has been synthesized. • Single Crystal X-Ray diffraction study revealed a trimeric structure linearly bridged by azide ion. • The fluorescent probe has been found to exhibit a cyan blue fluorescence getting 'turned-off' in presence of Cd2+ selectively. • A naked-eye visible colour change from pale yellow to colourless is observed. • Single crystal of Cd-substituted complex have been isolated and verified with single crystal XRD and computational calculations. • Selective Cd2+ probe with a very low detection limit of 1.72 nM enables its genuine implications in pollution management. Alarmingly increasing population and industrial growth has immensely affected water bodies and potable water sources by elution of many heavy toxic metal ions, including cadmium (II). The rising threat has demanded easy and cost-effective detection of this heavy metal ion so as to spread widely across the masses and eliminate the poisoning of water. With this aim, we have synthesized a zinc-based fluorescent probe (rBDZn) having reduced Schiff base backbone with N- and O- donor atoms derived from 5-bromosalicaldehyde and 2,2-dimethylpropane-1,3-diamine, characterized with the aid of single crystal X-ray analysis, revealing a trimeric structure linearly bridged by azide ion. The complex has been found to exhibit a cyan blue fluorescence getting 'turned-off' in the presence of cadmium ion selectively along with many other cations in the aqueous solution together with a naked-eye visible color change from pale yellow to colorless. Steady-state and time-resolved fluorescence titration, and absorption titration experiments were performed. During the investigation of the sensing pathway it is observed that the detection of Cd2+ is being associated with the formation of the cadmium complex rBDCd from the probe rBDZn and this has been explained though a probable mechanism. In support of the fact a single crystal of Cd-substituted complex have been isolated and verified with single crystal XRD and computational calculations. Proper justification of the selectivity of the probe towards cadmium ion with a very low detection limit of 1.72 nM enables its genuine impact in the pollution management. [ABSTRACT FROM AUTHOR]

[Display omitted] • New copper(I) Schiff base complex was synthesized and characterized. • Crystal structure of Cu(I) complex by single crystal X-ray diffraction technique was examined. • Catalytic activity of the Cu(I) complex was executed in the first-time synthesis of new tetrahydropyrimidine derivatives. • A mechanism for the catalytic reaction was suggested and investigated by density functional theory (DFT). Herein, we report the synthesis and spectroanalytical characterization of one-dimensional polymeric Cu(I) complex [Cu(L2Br)I] n , incorporating N,N′ -bis(2-bromobenzylidene)ethane-1,2-diamine Schiff base ligand, L2Br. Single crystal X-ray diffraction (SC-XRD) was used to examine the specific organization of atoms in the complex. The results showed that the Cu ion was coordinated only through the N donor sites of the Schiff base. The complex's tetrahedral shape was distorted, as demonstrated by the bond angles around the metal atom. The natural bond orbital and atoms in molecules investigations were also carried out in order to gain greater knowledge of the Cu(I) complex's intermolecular charge transfer characteristics. The redox nature of the the complex was assessed by the cyclic voltammetry (CV) technique. The Cu(I)/Cu(II) redox arrangement has been observed to exhibit characteristics consistent with a quasi-reversible method. Furthermore, the catalytic activity of the Cu(I) complex was executed in the first-time synthesis of new tetrahydropyrimidine derivatives by treating various aryl nitriles with 2,2-dimethyl-1,3-propanediamine under conventional thermal conditions. A mechanism for the catalytic reaction was suggested and investigated by density functional theory (DFT). [ABSTRACT FROM AUTHOR]

• The chemosensor MNP has been synthesized using 3-methoxy -5-nitro salicylaldehyde with N-Phenyl-o-phenylenediamine. • The MNP has the ability to detect Cu2+, F¯ and H 2 PO 4 ¯ ions using colorimetric and fluorometric "turn-off" techniques. • The solvatochromism of the MNP in the various solvents was examined. • The binding and molecular docking investigations of the MNP with BSA/HSA were examined. A new salicylidene-based chemosensor (E)- N 1-(2-hydroxy-3-methoxy-5-nitrobenzylidene)- N 2-phenylbenzene-1,2-diamine (MNP) has been developed by condensation of 3-methoxy-5-nitrosalicylaldehyde with N-phenyl-o-phenylenediamine and analysed using FT-IR, 1H-NMR and ESI-MS spectral techniques. The photophysical properties of MNP, including solvatochromism were investigated and the colour changed from bright yellow to red in the presence of water. This MNP specifically detects only Cu2+ with "turn-off" and a colour turned from light yellow to violet in CH 3 CN/H 2 O (9/1, v/v) mixture.The optimized geometry of the MNP-Cu complex was analyzed using DFT methods and the results is confirm the formation of the MNP-Cu complex. Besides, the F− and H 2 PO 4 −anions are preferentially sensed by the MNP in comparison to other anions, leading a "turn-off" and the colour change from light yellow to dark yellow in the THF medium. From the pH sensor data, the fluorescence intensity increased at pH 4.0 due to protonation of the -OH group. The interaction of the MNP with protein molecules (BSA, HSA) was investigated using absorption and emission spectral methods. The investigation computed values of the binding constant and the Stern-Volmer quenching constant demonstrated that the MNP had a far stronger affinity for BSA than for HSA. The interaction of the MNP with protein molecules was confirmed using docking studies. [Display omitted] [ABSTRACT FROM AUTHOR]

Despite the enormous use of polyurethanes (PUs) in multiple aspects of modern lifestyle, the industrial scale manufacturing of PUs uses toxic chemicals like isocyanates, phosgene till today. In addition, the non-biodegradability and non-biocompatibility of PUs and their debris are serious cause of concerns for the environment. To deal with these challenges, in the current work, a new approach is reported in which bio-derived non-isocyanate polyurethanes were synthesized by exploiting viable amino acid-based diamines and biscyclocarbonates from sebacoyl chloride and diglycerol derivatives in a readily doable process. The newly designed polyhydroxyurethanes (PHUs) exhibited remarkable biodegradability and biocompatibility (cell viability) in comparison with commercial diamine based PHUs. A series of PHUs were synthesized in bulk and solvent free green synthetic route by polycondensing library of amino acids (such as glycine, alanine, valine, and isoleucine etc.) based diamines consisting of varying alkyl chain lengths and biscyclocarbonates like sebacic biscyclocarbonate and diglycerol biscyclocarbonate etc. All the synthesized PHUs were thoroughly characterised by IR, NMR and HRMS spectroscopic techniques. The impact of chain length and molecular structure of the synthesized PHUs were also evaluated using DSC, TGA, SEC, water contact angle measurements and hydrolytic degradation studies. The molar masses of the PHUs obtained from the SEC analysis are in the range of ∼17,000–24,000 Da. The current study demonstrated that amino acids is one of the major degradation products and are biocompatible in in-vitro conditions. The PHUs and their degradable products showed excellent cell viability when studied in HEK293T cells that were carried out using microgram to milligram concentration of PHUs. The outcome of this work in comparison to conventional PHUs and polyurethanes clearly demonstrated good biocompatibility and hence drawing attention to potential applications in bio-adhesives, bio-implants, drug delivery, and green coatings etc. in the near future. [Display omitted] • Non-isocyanate polyurethanes are synthesized in a solvent free green synthetic route. • Amino acid derived monomers are prepared in a phosgene-free methods. • Synthesized polyhydroxyurethanes and their degraded products display remarkable biodegradability and biocompatibility. [ABSTRACT FROM AUTHOR]

• Different electronic and steric effects of amine backbone led to linear-type M-Dy-M, one-dimensional (1D) chain and interlayer-type structures of complexes. • Align the magnetic easy axis of lanthanide ions as closely as possible with the direction of M-M facilitating the mitigation of quantum tunneling of magnetization. • Notable hysteresis loops at maximum temperature of 3.5 K, 7.5 K, and 4 K are observed for Cu 2 Dy, Zn 2 Dy and Ni 2 Dy complexes, respectively. Series of 3d-4f heterotrinuclear complexes [ M Dy M ] (M =Zn, Cu, Ni) with formula [Cu 2 (L1) 2 DyCl 2 (H 2 O)]·Cl·MeCN (1), [Cu 2 (L2) 2 DyCl 2 ] n (2), [Cu 2 (L3) 2 DyCl 2 (MeOH) 2 ]·Cl·(MeOH) 3 (3), [Zn 2 (L1) 2 DyCl 2 (H 2 O)]·Cl·MeCN (4) and [Ni 2 (L1) 2 DyCl 3 ]·(CH 2 Cl 2) 2 (5) were constructed by three hexadentate compartment Schiff bases (L1 = N ,N'-bis(3-methoxysalicylidene)-2,2-dimethylpropane-1,3-diamine; L2 = N ,N'-bis(3-methoxysalicylidene)-1,3-propanediamine; L3 = N ,N'-bis(2‑hydroxy-3-methoxybenzylidene)-1,2-phenylenediamine). Different electronic and steric effects of amine backbone lead to linear-type M -Dy- M , one-dimensional (1D) chain and interlayer-type structures of complexes 1 – 5 , respectively. Among these, complexes 1, 4 and 5 were constructed as the M -Dy- M linear-type coordination configuration containing diamagnetic zinc(II) ions and paramagnetic copper(II) ions or nickel(II) ions respectively. Molecular magnetic studies reveal that complexes 1, 4, 5 and chain complex 2 exhibited significant single-molecule magnets (SMMs) behavior and the notable hysteresis loops at maximum temperature of 3.5 K, 3 K, 7.5 K, and 4 K are observed, which are comparable among the outstanding heteronuclear (d/f) SMMs constructed by Schiff base ligands. Series of 3d-4f heterotrinuclear [MDyM] SMMs were constructed, different electronic and steric effects of amine backbone lead to very different structure and displaying significant magnetic relaxation with hysteresis loops at maximum temperature of 3.5 K, 3 K, 7.5 K, and 4 K, respectively, which are comparable among the outstanding heteronuclear (d/f) SMMs constructed by Schiff base ligands. [Display omitted] [ABSTRACT FROM AUTHOR]

• Covalent attachment of l -tryptophan to modified MCM-41 leading to l -Tryp-N-pMCM-41. • Use of l -Tryp-N-pMCM-41 as catalyst for the synthesis of a series of quinoxalines. • Facile recovery and reuse of catalyst with no perceptible loss of activity. • Environmentally friendly protocol to access diverse azaheterocyclic scaffolds. An unprecedented strategy has been developed to introduce l -tryptophan into MCM-41 by binding the indolic NH group of l -tryptophan to modified MCM-41, resulting in the creation of l -Tryp-N-pMCM-41. Initially, 3-Cl-pMCM-41 was prepared by modifying activated MCM-41 with 3-chloropropyltrimethoxysilane. Subsequently, the covalent attachment between the indolic NH group of l -tryptophan and 3-Cl-pMCM-41 was achieved using n‑butyl lithium in THF at -78 °C under an argon atmosphere. l -Tryp-N-pMCM-41 has been characterized by FT-IR, XRD, TGA, EDS, BET and nitrogen physisorption measurements. The organocatalytic performance of this chemically stable material was assessed in the synthesis of both symmetrical and unsymmetrical quinoxalines. The reaction involved the condensation of a series of aromatic 1,2-diamines with 1,2-diketones in methanol at room temperature. Overall, the organocatalytic reaction proceeded smoothly to afford the corresponding quinoxalines in moderate to excellent yields. Furthermore, the crystal structure of an unsymmetrical quinoxaline has been determined by single crystal X-ray diffraction. This metal-free procedure offers several noteworthy advantages, including the simplicity of the reaction, minimal catalyst usage, recyclability of the catalyst and environmentally friendly characteristics. Moreover, this green heterogeneous organocatalyst is a suitable candidate for preparing various valuable pharmaceutical compounds under ambient conditions avoiding the use of strong acids and without any possibility of metal contamination. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Biphasic solvents can decrease the regeneration energy of CO 2 capture. As an intramolecular hybrid diamine, 3-Dimethylaminopropylamine (DMAPA) had a primary amino group and a tertiary amino group, which could absorb CO 2 by combining zwitterion and base-catalyzed hydration mechanism. The derived DMAPA/ n -PeOH/H 2 O biphasic absorbent possessed high CO 2 absorption capacity (1.46 mol/mol) and large CO 2 -rich phase loading (6.27 mol/L), which were superior to existing mixed amine systems. At 393.15 K, this system had a large desorption amount of 4.91 mol/L and a fast desorption rate (6.68 E-3 mol/L·s), which were 2.84 and 3.73 times of 30 wt% MEA. The associated total regeneration energy was reduced to 1.36 GJ/t CO 2 , only 34.1 % of MEA absorbent. The reaction mechanism and origin of phase separation were revealed by NMR analysis and quantum chemistry calculations. In addition, low viscosity and corrosiveness were revealed and conducive for industrial application. [ABSTRACT FROM AUTHOR]

The strong excitonic effect is widely prevalent in covalent organic frameworks (COFs)-based catalysts, while the high exciton binding energies (E b) of COFs seriously limit their photocatalytic performance. Herein, theoretical calculations are conducted to evaluate the E b values of potential COFs derived from benzo[1,2-b:3,4-b'-b'']trithiophene-2,5,8-tricarbaldehyde (BTT) and 2,4,6-trihydroxybenzene-1,3,5-tricarbaldehyde (Bp) as aldehyde monomers. Diverse aromatic amine linkers including dipyridine diamine (BPy), biphenyl diamine (BPh), and p -phenylenediamine (MPh) with different molecular lengths and N-sites are used as linker models to regulate the excitonic effect. The obtained BTT-BPy-COF with a long BPy linker and the lowest calculated E b value possesses the best photocatalytic performance for benzylamine coupling, with conversion and selectivity up to 99% accompanied by a high oxidation rate, outperforming most of the reported works. Further mechanistic investigation reveals that the bipyridine-N sites in BTT-BPy-COF exhibit strong electron transfer as well as enhanced O 2 adsorption and activation that is beneficial to photocatalytic benzylamine coupling. [Display omitted] • Different aromatic amine linkers are used to regulate the excitonic effect of COFs. • Photocatalytic performance of the obtained COFs closely relates to their E b values. • BTT-BPy-COF with low E b value and pyridine-N linker shows best catalytic activity. [ABSTRACT FROM AUTHOR]

With the increasing attention to environmental issues and sustainable development, bio-production of diamines from renewable raw materials is very important for the establishment of a sustainable nylon industry. A three carbon linear chain diamine, 1,3-diaminopropane (1,3-DAP), is an important platform chemical and has the potential for novel types of polyamides preparation. In this study, the C 4 biosynthetic pathway for 1,3-DAP reported before was introduced into Escherichia coli W3110 and homolog mining of 2-ketoglutarate 4-aminotransferase genes was conducted to increase 1,3-DAP production. We demonstrated that aminotransferase RocD from Bacillus subtilis 168 was the most effective one among the candidates. Meanwhile, l -aspartate transporters such as GltP from E. coli, GltP and GltT from B. subtilis 168 were examined to further improve the 1,3-DAP production. Subsequently, the dual-vector systems were introduced to the host to co-express aminotransferases from different sources and the engineered E. coli W3110 could accumulate 302 mg/L of 1,3-DAP with a yield of 0.31 mol/mol (1,3-DAP/ l -aspartate) on the shake flask cultivation. The strategies reported here will be useful for the efficient and sustainable bio-based production of 1,3-DAP. • Aminotransferase RocD was first used for efficient production of 1,3-diaminopropane. • l -aspartate transporter GltTbsu improved 1, 3-diaminopropane production by 23.03 %. • Two-aminotransferase system increased 1, 3-diaminopropane titer to 302 mg/L. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis and characterization of two new mononuclear Cu(II) complexes derived from N-donor ligands. • Comparison between mononuclear tridentate and pentadentate Cu(II) complexes. • Copper complex as a promiscuous catalyst. • Interaction and cleavage of the BSA protein mediated by a Cu(II) complex. • Cytotoxic activity of a Cu(II) complex in two cancer cell lines. In this work, we describe the synthesis and structural and spectroscopic characterizations of two copper(II) complexes, [(Cu)(L1)(Cl 2)].4H 2 O (1), where L1 is 2-(pyridin-2-yl)-1,3-bis(pyridin-2-ylmethyl)-hexahydropyrimidine, and [Cu(L2)](ClO 4) 2 (2), where L2 is N1,N1,N3-tris(pyridin-2-ylmethyl)propane-1,3-diamine. The crystalline structure analysis indicates that both complexes are mononuclear and pentacoordinated compounds. In the case of complex 1 , it bears a neutral charge, with the ligand coordinating to the Cu(II) center in a tridentate manner, utilizing N -donor atoms. Additionally, two cis -chlorido ligands completing the coordination sphere. On the other hand, complex 2 is a cationic complex, with the ligand coordinated in a pentadentate manner, with only N -donor atoms for coordination around the Cu(II). Complex 1 showed catalytic promiscuity, displaying hydrolytic and oxidative activity. The hydrolytic activity was investigated using bis(2,4-dinitrophenyl) phosphate (2,4-BDNPP) as a phosphodiester substrate and applying the Michaelis–Menten approach, obtaining the following kinetic parameters: k cat = 1.21 × 10-4 s−1; K M = 3.35 × 10-3 molL-1. Complex 1 also accelerates the oxidation of the 3,5-di- tert -butylcatechol (3,5-DTBC) substrate with catalytic efficiency equal to 6.11 L mol-1s-1. Interestingly, we demonstrated that this Cu(II) complex 1 can also cleave the very stable peptide bonds from BSA (bovine serum albumin) through an oxidative mechanism using ascorbate as a reducing agent. Complexes 1 and 2 show good cytotoxic activity against two cancer cell lines: A431 from human squamous cell carcinoma and K562 from chronic myeloid leukemia. This study showed that complexes 1 and 2 are selective towards cancer cells. [ABSTRACT FROM AUTHOR]

Although amide lubricants are commonly used as lubricants for acrylonitrile-butadiene-styrene (ABS) resins, the relationship between their structure and lubricating properties remains unclear. In this paper, a series of stearic acid diamide lubricants for ABS resins were synthesized through an amidation reaction with the stearic acid and aliphatic diamines. The chemical structure was characterized by FTIR and 1H NMR. A detailed evaluation of the lubrication effect of the lubricant was carried out by dynamic mechanical analysis, rotational rheometry, contact angle measurements, and so on. The results showed that the complex viscosity, glass transition temperature and diamine's alkyl chain length of stearic acid diamides were positively correlated, while the elongation at break displayed a negative correlation. Compared to ethylenediamine bis stearate acid (EBA), 1,8-diaminooctane bis stearate acid (OBA) exhibited a 37.8 % increase in the complex viscosity at 0.1 rad/s, along with a 4.6 % rise in the glass transition temperature. It was indicated that the lubrication effect of stearic acid diamides deteriorated with the increase of the alkyl chain lengths of diamines. The lubrication mechanism was further validated by molecular dynamics simulations. As the alkyl chain lengths of diamines increased, the mean square displacement and interaction energy of the system exhibited a tendency to become lower and higher, respectively. This meant that the longer alkyl chains of the diamines in the lubricants were not advantageous to the free mobility of the matrix molecular chains. These findings provided insightful guidance for the sensible design of lubricants for ABS resins. [Display omitted] • A series of stearic acid diamide lubricants for ABS resins were designed and synthesized. • The effect of alkyl chain structure in lubricants on lubrication properties was investigated. • Structure-property relationships of lubricants were revealed by combination of experiments and simulations. [ABSTRACT FROM AUTHOR]

This study explores the structure-property relationships in colorless polyimides (CPIs) synthesized from stereoisomeric (exo - and endo -form) alicyclic dianhydrides, combined with various diamines. The structural configurations of 5,5'-(1,4-phenylene)bis[hexahydro-(3aR,4R,5R,7S,7aS)-rel-4,7-Methanoisobenzofuran-1,3-dione] (BzDA- exo) and 5,5-(1,4-phenylene)bis(hexahydro-4,7-methanoisobenzofuran-1,3-dione) (BzDA- endo) were confirmed as exo - and endo -forms, respectively, through 1H NMR and 2D NOESY NMR analyses. Wide-angle X-ray scattering (WAXS) data revealed that stereoisomeric structures influence polymer chain packing in synthesized CPIs. The investigation extended to the chemical and physical structure-dependent properties such as physical, thermal and optical properties of the PIs. Notably, structure-dependent physical and thermal properties were evident, with a particularly strong structure-property relationship manifesting in the coloration and yellow index (Y.I.) of PIs. These systematic characterizations offer profound insights into the design and optimization of chemical and physical structures in CPIs, highlighting the versatility of stereoisomeric monomers for various applications. [Display omitted] • Systematic characterization of structure-property relationships in CPIs from stereoisomeric anhydrides with various diamines. • Significant effects of stereochemical configurations on the mechanical, thermal, and optical properties of colorless polyimides. • Effects of varying chain packing structures, due to different monomers, on mechanical and optical properties. [ABSTRACT FROM AUTHOR]

• Valorization of furfural (FF) and 5-hydroxymethylfurfural (HMF) as renewable sources for electrosynthesis. • Electrochemical monitoring of the reactivity of FF and HMF with aliphatic primary (di)amines. • Controlling feature: number of H-atoms at the α-carbon close to the amine nitrogen. • Pilot study for "one-pot" reductive amination in water solutions. • Vicinal diamine (analogue of a pinacol) together with furfurylamine are identified as products. Furfural (FF) and 5-hydroxymethylfurfural (HMF) are important and prospective renewable sources for chemical, fuel, material or pharmaceutical industry, the furfurylamines being the desired precursors. In this contribution new effects related to the reactivity of FF and HMF with various aliphatic primary (di)amines were observed using an electrochemical approach in water solutions. Following an initial investigation of electroreduction, the course of condensation reactions in basic buffers under various stoichiometric conditions was electrochemically monitored. Using five aliphatic amines and two (α,β- and α,ω-) diamines, a variety of products (mainly Schiff-bases) was identified. As a pilot study for "one-pot" reductive amination, the mixture of FF and n -PrNH 2 was electrochemically reduced in basic buffers. The vicinal diamine (analogue of a pinacol) was the main product, together with the expected furfurylamine. [ABSTRACT FROM AUTHOR]

In this study, a novel and facile one-step synthesis route was conducted to prepare semi-aromatic polyamide elastomer (PAPXD/1214-PEA) with p-phenylenediamine, dodecane diamine, dodecanedioic acid and polyether amine (PEA) as monomers. A systematic investigation has been conducted into the effect of hard segment content on the thermal, mechanical and solvent resistance of polymers when semi-aromatic polyamides are used as hard segments. It was found that the melting point of the copolymers gradually increased from 191.2 °C to 231.5 °C with the hard segment content increased from 39 % to 76 %, while the Vicat softening temperature (VST) enhanced from 103.2 °C to 192.2 °C. Compared with the commercial polyamide elastomer Pebax@ (produced by Arkema Inc) with similar hard segment contents, the VST of PAPXD14/1214-PEA were 17.4–66.2 °C higher. The mechanical performance of these elastomers was also largely improved with tensile strength increasing from 15.1 to 40.6 MPa, Young's modulus from 28.2 to 168.7 MPa, toughness from 91.1 to 170.7 MJ/m3. In addition, the solvent resistance properties of PAPXD14/1214-PEA was compared with the commercial polyamide elastomer Pebax@. After soaking in hydrochloric acid for 24 h, the tensile strength of PAPXD/1214-PEA with the hard segment content increased from 50 % to 63 % decreased down to 9.4 and 14.4 MPa, respectively. While the commercial polyamide elastomer Pebax@ (with similar hard segment content) decreased down to 1.5 and 4.3 MPa, indicating the commercial polyamide elastomer products were deteriorated. This suggests the corrosion resistance of the synthesized PAPXD/1214-PEA is much better than that of commercial product, and these semi-aromatic polyamide elastomers can be potentially applied in some harsh service environment especially for high temperature and corrosion sealing. [Display omitted] • Polyamide elastomers were synthesized with a facile one-step method. • Polyamide elastomers have good thermal, mechanical properties than past elastomers. • Polyether amines increase corrosion resistance of polyamide elastomers. [ABSTRACT FROM AUTHOR]

Polyethylene-based covalent adaptable networks (PE CANs) are obtained by reactive extrusion in a micro-compounder of a commercial maleic anhydride-grafted polyethylene (PE- g -MA) with two tailor-made α,ω-diamine cross-linkers carrying either imine or 1,2,3-triazolium groups as dissociative covalent dynamic bonds. Depending on the chemical nature of the exchangeable bonds, drastically different properties are demonstrated by FTIR, swelling/extractible, reactive dissolution and rheological experiments. The imine-containing PE CAN yields a high gel fraction but rheology and reactive dissolution experiments demonstrate the lack of dynamicity due to side-reactions promoting the formation of non-dynamic covalent cross-links. Such undesirable reaction occurs already during the processing stage from the premature cleavage of the imine bonds into amines, and further formation of permanent imide cross-links by reaction with pendent maleic anhydrides. Conversely, the 1,2,3-triazolium-containing PE CAN presents a lower gel fraction but exhibits viscoelastic properties typical of dissociative CANs. While this material is easily reprocessable by compression moulding, the evolution of the rheological properties at high temperatures (160–200 °C) points toward the occurrence of side reactions slowing down the relaxation dynamics which we attribute to the chemical rearrangement of the 1,2,3-triazolium cross-links. These two examples illustrate the difficulty of using amine -functionalized dynamic cross-links in the synthesis of PE CANs by reactive extrusion using PE- g -MA. [Display omitted] • Imine- and 1,2,3-triazolium-containing diamine cross-linkers are synthesized. • Polyethylene-based covalent adaptable networks are prepared by reactive processing. • Amine groups react with pendent anhydrides from a commercial polyethylene. • Orthogonality between grafting and exchange reactions is discussed. [ABSTRACT FROM AUTHOR]

• Synthesis of novel diamine-based Schiff bases. • Structural confirmation through various spectroscopic techniques. • Exploration of optical nonlinearity via DFT. • Study of key electronic properties at M06/6-311G (d,p) functional. • Utilization of TD-DFT approach for FMOs and UV–Vis analyses. The study focuses on the synthesis and theoretical investigation of a series of newly synthesized diamine-based Schiff bases. Structural confirmation of the synthesized Schiff bases was achieved through various spectroscopic techniques. DFT calculations, utilizing the M06/6311G (d, p) functional, were conducted to assess NLO characteristics. The broader absorption spectrum (444.0 nm) and a smaller bandgap (4.4 eV) were observed for compound:1E,1′E)- N,N '-(1,4-phenylene)bis(1-(4-nitrophenyl)methanimine compared to the other synthesized compounds. The NBOs results provided insight into the hyperconjugative phenomenon that contributes to the stability of entitled compounds. Among all the examined compounds, 1E,1′E)- N,N' -(1,4-phenylene)bis(1-(4-nitrophenyl)methanimine exhibited the highest value (3.7 × 10−29 esu) for first hyperpolarizability (β tot). Moreover, the calculated first hyperpolarizability for the newly synthesized diamine-based compounds is greater than standard para -nitroaniline. Above findings ascertained the potential of synthesized compounds for advanced applications in high-tech NLO technologies. [ABSTRACT FROM AUTHOR]

When introducing acid groups in the diamine monomer for the fabrication of polyamide (PA) membranes through interfacial polymerization (IP), the acid groups not only reduce the diffusion flux of diamine monomer for the polymerization to prepare ultrathin membrane but also provide the negative charges on the membrane surface. However, the introduction of acid groups often weakens the reactivity of diamine monomers, resulting in the formation of thick and loose PA membranes with low rejection of ions. This study proposes a strategy of modulating the IP process of piperazine-2-carboxylic acid (CPIP) by employing an acid acceptor (NaOH) to prepare thin nanofiltration membranes. The acid acceptor can neutralize the HCl to prevent CPIP from being protonated during the IP process, thereby facilitating the cross-linking reaction rate. The thickness of the resulting membrane decreases from 180 nm to 30 nm, accompanied by the fortification of the negative charge, an increase in cross-linking density, and a reduction in pore size. The resulting PA-AA/CPIP_1.0 membrane exhibits a water permeance of 44.6 L m−2 h−1 bar−1, with a significantly increased Na 2 SO 4 rejection of 98.4 % compared with 50.4 % of the PA-AA/CPIP_0 membrane fabricated without acid acceptor. This work may open a new avenue to fabricating high-performance PA membranes for nanofiltration. [Display omitted] • Acid acceptors promote the IP process of piperazine-2-carboxylic acid and TMC. • Membrane thickness is decreased and surface negative charge is increased. • Membrane cross-linking density is increased along with the reduced pore size. • The PA-AA/CPIP_1.0 membrane exhibits high Na 2 SO 4 rejection and water permeance. [ABSTRACT FROM AUTHOR]

• Transformation of fluorinated 1,2-phenylenediamines was investigated in PPA. • Asymmetrically fluorinated 2,2′-bibenzimidazoles were obtained. • Under similar conditions phenazine-2,3-diamines were obtained. • The direction of the reaction depends on the number and position of f atoms. • Hydrodefluorination of initial diamines occurs when f contain at 4 and 5 positions. A series of asymmetrically fluorinated 2,2′-bibenzimidazoles were obtained by reaction of benzimidazole-2-carboxylic acid with fluorinated 1,2-phenylenediamines in polyphosphoric acid at elevated temperature. The tautomers of fluorinated 2,2′-bibenzimidazoles with a predominance of isomers containing F atoms in distant position relative to the NH group of the benzimidazole fragment are detected in DMSO‑d6 using NMR spectroscopy. The ratio of tautomers depends on the number and arrangement of F atoms in the initial fluorinated 1,2-phenylenediamines. Under similar conditions fluorinated 1,2-phenylenediamines in the presence of benzimidazole-2-carboxylic acid, but without its participation as well as without it, give fluorinated phenazine-2,3-diamines. The direction of transformation of fluorinated 1,2-phenylenediamines depends on the number and position of F atoms. Under similar conditions phenazine-2,3-diamine is not formed from non-fluorinated 1,2-phenylenediamine, but it is obtained with the presence of fluorinated 1,2-phenylenediamines. When fluorinated 1,2-phenylenediamines contain F atoms simultaneously at the positions 4 and 5, the hydrodefluorination of initial fluorinated 1,2-phenylenediamines occurs, resulting in less fluorinated 2,2′-bibenzimidazoles and phenazine-2,3-diamines. Hydrodefluorination of fluorinated 1,2-phenylenediamines in a polyphosphoric acid at elevated temperatures is the first example of the hydrodefluorination of fluorinated aromatic compounds containing strong donor substituents, such as amino groups. Polyphosphoric acid is shown to be a suitable medium for redox processes. [Display omitted] [ABSTRACT FROM AUTHOR]

We fabricated organic–inorganic lead chloride-based compounds with an ether diamine: (NH 3 C 2 H 4 OC 2 H 4 OC 2 H 4 NH 3)PbCl 4 (EDBEPbCl 4), (NH 3 C 3 H 6 OC 4 H 8 OC 3 H 6 NH 3)PbCl 4 (BBEPbCl 4), and (NH 3 C 3 H 6 OC 2 H 4 OC 2 H 4 OC 3 H 6 NH 3)PbCl 4 (DGBEPbCl 4). After the fabrication of these crystals, their luminescence characteristics were investigated. A broadband emission that might be derived from self-trapped excitons (STEs) was detected, and photoluminescence quantum yields of these crystals were 16 % (EDBEPbCl 4), 2.9 % (BBEPbCl 4), and 2.7 % (DGBEPbCl 4). In the scintillation spectra, a broadband peak was also observed from the fabricated crystals, and they exhibited a decay time of 12 ns (EDBEPbCl 4), 11 ns (BBEPbCl 4), and 11 ns (DGBEPbCl 4) in scintillation. Further, their pulse height spectra under alpha-ray were recorded using 241Am. The highest light yield was observed from EDBEPbCl 4 (2000 photons/5.5 MeV-α) and its light yield was higher than that of a zinc oxide single crystal. • We fabricated organic–inorganic lead chloride-based compounds with an ether diamine. • Broadband photoluminescence and scintillation were observed from the fabricated compounds. • (NH 3 C 2 H 4 OC 2 H 4 OC 2 H 4 NH 3)PbCl 4 showed the highest light yield of 2000 photons/5.5 MeV-α under alpha-ray. [ABSTRACT FROM AUTHOR]

[Display omitted] A three-component protocol was adopted to efficiently prepare new bis(pyrazolo[1,5- a ]pyrimidines) linked to different spacers in 80-92% yields from 1 H -pyrazole-3,5-diamines, malononitrile and bis(aldehydes). The p -xylene-linked bis(pyrimidine) bearing 3-positioned 4-methoxy-benzyl substituent had the best antibacterial activity with MIC / MBC values up to 2.2 / 4.4 µm. [ABSTRACT FROM AUTHOR]

• The polycondensation route yields the finest polyazomethines (NAZ) at room temperature. • The dicarbaldehyde monomer and diamines produce the best NAZ material. • The polyazomethine electrode demonstrates the highest specific capacitance at 860 Fg−1. • The as-prepared polyazomethine has demonstrated the highest power density and remarkable stability. A polyazomethine, designated as NAZ, was synthesized effortlessly at room temperature via a highly efficient polycondensation route employing 5,5′-(4-nitro-1,2-phenylene)bis(furan-2-carbaldehyde) (III) as a monomer, along with a diverse array of diamines meticulously selected for engineering the NAZ polyazomethine. The resulting NAZ material underwent a comprehensive characterization employing cutting-edge techniques including X-ray diffraction (XRD), the random morphology of polyazomethine has revealed in FESEM and TEM images, energy dispersive X-ray analysis (EDAX), and a suite of advanced spectroscopic methods. In the realm of Fourier-transform infrared spectroscopy (FTIR), the emergence of the distinctive –CH N– peak at 1608 cm−1 unequivocally validated the triumphant conversion of dicarbaldehyde (III) and diamines into the desired polyazomethine structure. XRD diffractograph unveiled the tantalizingly amorphous disposition of NAZ, while the FESEM images elegantly revealed its enigmatic and inherently random morphology. The EDAX analysis, meanwhile, provided an exquisite insight into the intricate chemical composition and elemental distribution meticulously orchestrated on the surface of NAZ. Delving into the electrochemical domain, the synthesized polyazomethine electrodes were subjected to a rigorous battery of tests including cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and the formidable electrochemical impedance spectroscopy (EIS). The superlative supercapacitive prowess of the NAZ electrodes were fervently evaluated across a plethora of electrolytic environments encompassing NaOH, LiCl, NaNO 2 , and the venerable KOH, spanning an impressive range of concentrations. Noteworthy is the awe-inspiring performance of the NAZ electrode in the hallowed 1 M KOH electrolyte, boasting an unprecedented specific capacitance (Cp) of 860 Fg−1, specific energy (SE) soaring to an impressive 6.14 Whrkg−1, and specific power (SP) scaling the summit at a staggering 74 KWkg−1, thus epitomizing optimal performance in every facet. Furthermore, the indomitable NAZ electrode exhibited an unparalleled degree of stability, steadfastly retaining a remarkable 69.25 % of its initial capacitance even after being subjected to the rigorous crucible of successive 1000 cycles within the exacting confines of the 1 M KOH electrolyte. [ABSTRACT FROM AUTHOR]

In the upcoming decades, the incidence and mortality rates of cancer are expected to rise globally, with colorectal and prostate cancers among the most prevalent types. Despite advancements in molecular targeted therapy, platinum-based chemotherapies remain the cornerstone of treatment, especially for colorectal and prostate cancer, with oxaliplatin and cisplatin being extremely effective due to their DNA-targeting capabilities. In our pursuit of new platinum-based chemotherapeutics that are potentially less toxic and more effective, we have explored the combination of the Pt-binding groups of the diaminocyclohexane ring used in oxaliplatin, with the stable amino-pyrimidine hemicurcumin moiety. This new derivative exhibit improved stability in physiological conditions and increased solubility in aqueous media, demonstrating promising effects on cell proliferation of both colorectal and prostate cells. We report herein the complete synthesis and chemical characterization in solution of the new derivative [(1 R ,2 R)-N1-(3-(4-((E)-2-(2-Amino-6-methylpyrimidin-4-yl)vinyl)-2-methoxyphenoxy) propyl) cyclohexane-1,2-diamine] (MPYD). Our analysis includes an examination of its acid-base equilibria, speciation and stability in physiological conditions. The synthesis and in situ formation of Pt(II) complexes were investigated by nuclear magnetic resonance spectroscopy, while density functional theory calculations were employed to elucidate the chemical structure in solution. Results on the biological activity were obtained through cell viability assays on different colorectal and prostate cell lines (HCT116, HT29, PC3 and LNCaP). A new N,N chelator for Pt(II): Amino-pyrimidine hemicurcumin bridged to diaminocyclohexane. Is the match improving or detrimental to the anticancer activity? How chemical investigations can rationally help to address this task. [Display omitted] • Amino-pyrimidine hemicurcumin bridging diaminocyclohexane: a new N,N chelator for Pt(II). • Greater stability in physiological conditions than the lead compound Curcumin. • Pt(II) complex formation in solution by NMR and DFT calculations. • Amino-pyrimidine hemicurcumin moiety enhances cellular uptake of Pt complex. • Pt complex mainly affects replication phase in HCT116 cancer cells. [ABSTRACT FROM AUTHOR]

Dual-enzyme co-embedded materials have shown high potential for achieving efficient detection due to the convenience of two-enzyme cascade reactions. Herein, we developed a dual-enzyme hybrid microsphere (HM) based biosensor to detect diamines (histamine was included for ease of description) in aquatic products. The HM was made from diamine oxidase, horseradish peroxidase, and copper phosphate through the biomineralization method. Under optimal conditions, the system displayed linear color response to histamine of different concentrations ranging from 0 to 200 μg/mL. The detection limit of histamine was 0.15 μg/mL, showing higher sensitivity than the two-step free enzyme assay. Moreover, the detection system exhibited good specificity to diamines. The method was used to detect diamines in commercial samples, and the results were compared with those measured by the high-performance liquid chromatography method. Overall, the proposed assay exhibited high potential in diamine quantification and was readily extended to other cascade enzymatic reaction-based detection strategies. • Dual enzyme-inorganic hybrid microsphere was synthesized through bio-mineralization. • A sensor-based on hybrid microspheres and TMB were constructed for detecting diamine. • Good sensitivity, specificity, and visual sensing have been obtained. • This sensor has promising detection performance in aquatic products. [ABSTRACT FROM AUTHOR]

Scheme. 1. Illustration of (a) static procedure and (b) dynamic procedure for analysis of naphthalene and its derivatives. [Display omitted] • MDA was used as a linker monomer to prepare flexible COFs for the first time. • TpMDA showed high removal efficiency to naphthalene and its derivatives. • TpMDA remained well adsorption capacity after 10 times desorption/adsorption cycles. • Possible adsorption mechanisms were discussed in detail. • TpMDA had promising applications in the removal of linear and planar PAHs. In this work, a flexible covalent organic framework (named TpMDA) was prepared by cheap 4,4′-diaminodiphenylmethane (MDA) monomer with flexible methylene groups. TpMDA could realize efficient removal of naphthalene and its derivatives (NAs) from environmental water samples through hydrophobic, π-π and electrostatic interactions. The superior adsorption and desorption performance of TpMDA was confirmed by static and dynamic adsorption/desorption experiments. It can be seen from the fitting results of the adsorption experiments that the adsorption of NAs was a spontaneous, endothermic, and comprehensive adsorption process that included both physical and chemical adsorption. The average removal efficiency of Nap, 1-Anap, 1-Nnap, 1-Naa and Npx by TpMDA from the four batches were 92.1 %, 86.9 %, 93.8 %, 75.3 % and 91.8 %, respectively. The maximum adsorption capacities were 301, 120, 184, 125 and 106 mg/g, respectively. In addition, TpMDA could be reused at least 10 times without degradation of adsorption performance. The selectivity for planar and linear molecules was verified. The feasibility of practical application was verified by static/dynamic adsorption volume experiments and the application of TpMDA in different aqueous environments. In general, this work not only proposes a new idea for the preparation of flexible COFs, but also provides a promising strategy for the removal of NAs in environmental remediation. [ABSTRACT FROM AUTHOR]

We report here on the structure-activity relationships of hybrids combining 3-descladinosyl clarithromycin with quinolones linked by extended diamine connectors. Several hybrids, exemplified by 23Bc , 23Be , 23Bf , 26Be , and 30Bc , not only restored potency against inducibly resistant pathogens but also exhibited significantly enhanced activities against constitutively resistant strains of Staphylococcus pneumoniae and Staphylococcus pyogenes , which express high-level resistance independent of clarithromycin or erythromycin induction. Additionally, the novel hybrids showed susceptibility against Gram-negative Haemophilus influenzae. Notably, hybrid 23Be demonstrated dual modes of action by inhibiting both protein synthesis and DNA replication in vitro and in vivo. Given these promising characteristics, 23Be emerges as a potential candidate for the treatment of community-acquired bacterial pneumonia. [Display omitted] • The SARs of non-ketolides with extended sidechains at the 3-OH were illuminated. • The sidechain at 9-oxime resulted in synergistic effects that increase efficacy. • Compound 23Be demonstrated inhibitory effects on both DNA gyrase and ribosomes. • Compound 23Be exhibited improved potencies against constitutively resistant bacteria. [ABSTRACT FROM AUTHOR]

A novel type of triphenylamine derivatives, phenyl-bridged N , N , N ′, N ′-tetrasubstituted bis(2-amino-5-thiazolyl) diamine (4) and its cationic form (5) were synthesized via the Hantzsch reaction. The UV–Vis spectroscopy, cyclic voltammetry (CV) and density functional theory (DFT) calculation results showed that the diamine possesses excellent redox properties and a narrow optical energy gap (∼1.85 eV). As an electrochromic material, compound 4 exhibits a notable color change from colorless to blue. It maintains stable cycling performance for up to 175 cycles, even within a higher voltage range of −2.4 to 2.4 V. In addition, as a catalyst, compound 5 exhibits good substrate compatibility and an aniline conversion rate of up to 89 % during the photocatalytic reduction of nitrobenzene. These results would contribute to understand the synthesis of triphenylamine electrochromic materials and expand their applications in the field of photocatalysis. • A new type of triphenylamine derivatives phenyl-bridged N,N,N′,N′ -tetrasubstituted bis(2-amino-5-thiazolyl) diamine (4) and its cationic form (5) were synthesized through hantzsch reaction. • 4 exhibited good electrochemical stability, even at the higher voltage range of −2.4 to 2.4 V, it can still cycle stably for 175 cycles. • 5 exhibited good substrate compatibility and an aniline conversion rate of up to 89 % during the photocatalytic reduction of nitrobenzene. [ABSTRACT FROM AUTHOR]

[Display omitted] The selective protection of an aromatic amino group in the presence of aliphatic amino group in diamines by the action of FmocCl or CbzCl using liquid CO 2 as the solvent has been proposed. The developed method is preparative, does not require complex purification of the product, and meets the principles of green chemistry. [ABSTRACT FROM AUTHOR]

• Preparation of diverse DATNBI crystal structures through molecular self-assembly. • Introducing crystal defects to enhance the light absorption performance of DATNBI. • The self-sustaining combustion of DATNBI without photosensitizer under NIR laser is achieved. • The electron-hole recombination in the defect state is induced by laser radiation to enhance photothermal conversion. Although laser ignition is considered to be one of the most promising ways to detonate energetic materials due to its high safety and reliability, it is still a challenge to achieve direct ignition of energetic materials by a laser with low-power and near-infrared (NIR) band. In this paper, a molecular self-assembly strategy based on recrystallization was utilized to prepare 4,4′,5,5′-tetranitro-1H,1′H-[2,2′-biimidazole]-1,1′-diamine (DATNBI) crystals with various micro-nano structures. The characterization results suggest that DATNBI crystals with different degrees of roughness and defects by the induction of solvents and surfactants. The crystal defects can not only bring about the enhancement of light absorption of DATNBI in NIR band, but also advance its thermal decomposition, providing reliable support for direct laser ignition of DATNBI profit from the hot spot ignition theory. Combined with density functional theory, it is speculated that electrons of defect states achieve electron-hole recombination by laser radiation, thereby enhancing photothermal conversion. Compared with raw DATNBI, DATNBI crystals with rough surface and abundant defects can be directly ignited by a NIR laser and exhibits self-sustainable combustion. In summary, a direct NIR laser-ignitable energetic material has been prepared via appropriate crystal structure design. [ABSTRACT FROM AUTHOR]

• A new concept of SIP was proposed for the preparation of PEA NF membranes. • The reactivity of hydramine could be activated by a trace amount of diamine. • The "hydramine-diamine" coupling unit acts as the reactive monomer. • The PEA membranes exhibited an improved salt rejection and considerable PWP. Polyester-amide (PEA) thin film composite (TFC) NF membranes have rapidly evolved towards a competitive performance, benefiting from their remarkable antifouling capability and superior chlorine resistance. In this report, a new concept of synergistic interfacial polymerization is explored, which promptly triggers the reaction between hydramines and trimesoyl chloride (TMC) in the presence of a trace amount of diamines. This rapid-start mode enables the formation of defect-free PEA films without the requirement of catalysis. A comprehensive characterization of physicochemical properties using high-resolution mass spectrometer (HRMS) reveals that the recombination and formation of a "hydramine-diamine" coupling unit plays a decisive role in activating the synergistic interfacial polymerization reaction with TMC molecules. Taking the pair of serinol and piperazine (PIP) as an example, the PEA-NF membrane fabricated with 0.1 w/v% serinol mixed with 0.04 w/v% PIP as water-soluble monomer and 0.1 w/v% TMC as oil phase monomer was found to have a pure water permeability (PWP) of 18.5 L·m−2·h−1·bar−1 and a MgSO 4 rejection of 95.5 %, which surpasses almost all the reported PEA NF membranes. Findings of the current research provide more possibilities for the low-cost and rapid synthesis of high-performance PEA membranes aiming for water purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • The multicomponent polymerization of diamines, CS 2 , and diacrylates. • The synthesized polydithiourethanes could be efficiently degraded via aminolysis. • The prepared polydithiourethanes networks could be reprocessed. In the pursuit of advanced functional polymer materials, sulfur-containing polymers have received tremendous attention owing to their superior chemical stability, high refractive indices, various supramolecular interactions, and robust dynamic covalent chemistry. However, their synthesis usually involves either expensive monomers or toxic byproducts and requires catalysts, thus hindering their widespread application. In this work, we present a catalyst-free multicomponent polymerization in organic solvents for the synthesis of various polydithiourethanes with excellent yields (up to 98 %) and high molecular weights (up to 112 kg/mol). This reaction involves the direct polymerization of carbon disulfide, an abundant one-carbon feedstock, with commercially available diamines and diacrylates. This polyaddition process demonstrates high atom economy and no byproduct, occurring at room temperature without the need for a catalyst, thus exhibiting excellent green chemistry metrics. By utilizing the dynamic covalent chemistry of dithiourethane groups, these polymers can be efficiently degraded via aminolysis and used to fabricate reprocessable vitrimers. This multicomponent polymerization opens up a new avenue for the efficient utilization of carbon disulfide resources and accelerates the exploration of diversified sulfur-containing functional polymer materials. [ABSTRACT FROM AUTHOR]

1,6-Diazabicyclo[4.4.4]tetradecane benzo analog was synthesized from 2,11-diaza[3.3]- o -cyclophane. The other route gave 1-azonia-6-azatricyclo[4.4.4.01,5]tetradecane tribenzo analog. Key Topics: Synthesis of bicycloamine benzo analog. [Display omitted] 1,6-Diazabicyclo[4.4.4]tetradecane, which was extensively studied by Alder et al. in the 1970–1980 s, exhibits very interesting redox and protonation properties. We intended to synthesize its benzo analog as an extension of our studies on aza cryptands; however, by following Alder's synthetic route, we obtained only tricyclo[4.4.4.01,5]tetradecane tribenzo analog. Therefore, the target compound was synthesized from 2,11-diaza[3.3]- o -cyclophane. The proton-template synthesis of the benzo analog was straightforward and clean. The optimized structures of the products were obtained by DFT calculations since crystal structures were not available. The results showed that the N H+ proton of the ammonium salt was biased towards the nitrogen atom on one side. This is in contrast to the internally protonated 1,6-diazabicyclo[4.4.4]tetradecane · H+, in which the proton is located exactly halfway between two N atoms. Thus, the properties of the tribenzo analog is different from those of their parent aliphatic bicyclic diamine, and the basicity is comparable to that of ordinary amines. [ABSTRACT FROM AUTHOR]

Conventional thermosetting materials lack of reprocessability, acid-degradability, and fire-safety, which limit the further popularization and application of materials. In this study, a hexasubstituted cyclotriphosphazene (HVP) was synthesized from abundant renewable vanillin, and then combined with two bio-based amines (castor oil polyamine and furan-derived diamine) to establish polyimine networks through a condensation reaction between amino groups and aldehyde groups. Five bio-based polyimine thermoset networks (FA-0, FA-25, FA-50, FA-75, and FA-100) were prepared with an ammonia-formaldehyde ratio of 1:1, and varying the ratio of the two bio-based amines allowed for regulating the final mechanical properties (from tough plastic-like to hard plastic-like) and flame resistance of the materials. Among the five experimental samples, FA-100 exhibited the best physical properties stress and Tg of 28.47 MPa and 63.8 °C, respectively. FA-100 networks also showed the best flame retardant properties (LOI, 28.8 vol/%). Furthermore, due to the dynamic imine bonds in the polymer network, the material could be recycled under hot pressing conditions (120 °C and 15 MPa). Meanwhile, the monomer HVP could be recovered under mild acidic circumstances. These thermosetting polyimine networks provide a new avenue for the development of multifunctional bio-based polymer materials for practical applications. [Display omitted] • Five bio-based polyimine networks were successfully prepared. • The ratio of two bio-based amines affects the properties of polymers. • Phosphoronitrile units make the polymer exhibit flame retardant properties. • The dynamic imine bond gives the material multiple recovery properties. [ABSTRACT FROM AUTHOR]

Four new diamines (3TFDABA, 2TFDABA, 22TFDABA and TFAPTA) were successfully synthesized to investigate the effect of different trifluoromethyl (CF 3) substitution position on poly(amide-imide)s (PAIs) properties. High-performance PAIs were prepared from high-temperature polycondensation of these diamines with 6FDA dianhydride. All the PAI films exhibited good heat resistance with glass-transition temperatures (T g s) of 311–392 °C, good 5% weight loss temperatures (T d5% s) of 480–510 °C in nitrogen, and excellent optical transparency with T 450 ranging from 52% to 84%. According to the monomer structural design, a high heat resistant and colorless poly(amide-imide) film (PAI-2-6FDA), with excellent optical properties (T 450 of 82%), outstanding thermal properties (T d5% of 499 °C and T g of 392 °C), and good mechanical properties (tensile strength of 123 MPa, tensile modulus of 4.4 GPa) was achieved. A comprehensive structure-to-property relationship study revealed that the CF 3 in ortho -position of the amino group effectively inhibited the rotation between imide ring and benzene, thus improved the heat resistance of the film. Moreover, it could also weaken the generation of charge transfer complexes through strong electron-withdrawing ability, which is beneficial for the synthesis of colorless polyimides. [Display omitted] • Synthesis of four new diamines with different CF 3 substitution position along amide and amine moieties. • Structure property relationship of CF 3 substitution to influence the thermal and optical properties of polyamide-imides. • The CF 3 in ortho -position of the amino group exhibit the best properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • Polyamides with D-A segments for electrochromic and memory storage performance improvements. • The triphenylamine moiety with substituted methoxyl group improves the switching cycle stability. • Polyamides exhibit high optical contrast, outstanding coloration efficiency, fast response and long-term cycle. • Polyamides also serve as memristors with accessible threshold voltage and long retention time. With the aim to obtain multifunctional durable electrochromic (EC) devices, we propose an effective strategy by introducing weak electron acceptor segment with suitable bandgap and oxidation potential. A series of quinoxaline-based units polyamides (PAs) (denoted as T 2 BPA-CA, T 2 BPA-OA, T 2 BPA-TP, and T 2 BPA-SA) were prepared from a novel donor–acceptor-donor (D-A-D) type diamine with weak electron acceptor quinoxaline and connected with two methoxyl-substituted donor triphenylamine, 10,13-bis[4-aminophenyl (4-methoxyphenyl) amino]-dibenzo[a,c]phenazine, and four dicarboxylic acids, which are high soluble in various organic solvents and exhibit excellent thermostability. Furthermore, the T 2 BPA-SA thin film exhibits excellent EC performance with outstanding optical contrast (50 %), high coloration efficiency (230 cm2 C−1) and impressive cycle stability (optical contrast remains 80 % over 1400 cycles) in the NIR range. Meanwhile, all of these PAs are served as memristors and exhibit typical nonvolatile ternary memory, realizing an accessible threshold voltage of −0.65 V, a retention time of more than104 s and high current switch ratio (103.52:102.43:1). Overall, this work implies the great potential of these PAs in EC displays and memory storage devices. [ABSTRACT FROM AUTHOR]

In this paper, we present a synthetic strategy for N-phenyl substituted benzimidazole-derived diamines, including 2-(4-(4-aminophenoxy) phenyl)-1-phenyl-1H-benzo[d]imidazole-5-amine (para-diamine) and 2-(3-(4-aminophenoxy) phenyl)-1-phenyl-1H-benzo[d]imidazole-5-amine (meta-diamine). Two distinct series of N-phenyl substituted poly (benzimidazole imide)s (PBIPIs) were synthesized via reaction with different aromatic dianhydrides. The simulation reveals distinct amine reaction activities of two diamine monomers. The obtained PBIPIs exhibit exceptional heat resistance attributed to N-phenyl substituted benzimidazole (BI). The temperature at which weight loss of 5 % (T 5%) is in the range of 491–595 °C under N 2 environment, while the glass transition temperature is 237–329 °C. The PBIPIs exhibit specific solubility characteristics due to the flexible ether linkage groups' non-coplanarity and bulky pendant benzene groups. The PBIPIs possess tensile strength between 108 and 142 MPa, a tensile modulus of 4.0–5.9 GPa, and an elongation at a break of 4.2–26.4 %, indicating excellent mechanical properties. Additionally, the PBIPI with controlled molecular weight generated from BPADA incorporating 2-(3-(4-aminophenoxy) phenyl)-1-phenyl-1H-benzo[d]imidazole-5-amine (B-BPADA-PA) demonstrates exceptional melt processability. B-BPADA-PA possesses remarkable melt stability since its minimum complex viscosity is only 2100 Pa⋅s at 400 °C, and its melt viscosity ratio is 1.34 at 380 °C. [Display omitted] • The N-phenyl substituted benzimidazole-derived diamines were designed by a cleverly synthetic strategy. • The PBIPIs possessed excellent thermal resistance and superior mechanical properties. • The PBIPIs exhibited good solubility characteristics and extremely low water absorption. • B-BPADA-PA exhibited good melt processability with a minimum complex viscosity of 2100 Pa⋅s at 400 °C. [ABSTRACT FROM AUTHOR]

The development of efficient processes for value-added utilization of low-concentration CO 2 is an on-going challenge. In this work, we present a sequential system based on diamine platforms for the direct utilization of low-concentration sources of CO 2 (≤15%) in the production of cyclic ureas. Specifically, the low-concentration CO 2 is captured by ethylenediamine to form ethylenediamine carbamate (EDA-CA), which subsequently undergoes the intramolecular dehydration to give ethyleneurea (EU) in the presence of frustrated Lewis pairs (FLPs) on the facet-engineered CeO 2. Remarkably, the productivity of EU obtained from EDA-CA in the sequential system (9.5 mmol·g cat −1·h−1) is ∼4 times higher compared to the traditional catalytic system (2.4 mmol·g cat −1·h−1) using ethylenediamine and pure CO 2 (3 MPa). Density functional theory calculations demonstrated that the FLPs on facet-engineered CeO 2 significantly reduce the energy barrier for the nucleophilic attack of N-containing segment towards the carbonyl carbon in EDA-CA (rate-limiting step), ultimately optimizing the intramolecular cyclization efficiency of EDA-CA. This work not only provides an innovation tandem approach that enables the production of cyclic ureas from low-concentration CO 2 , but also opens up a promising avenue for the direct utilization of low-concentration CO 2 for value-added applications in the future. [Display omitted] • The synthesis of cyclic ureas from low-concentration CO 2 can be achieved via a diamine-based sequential system. • EDA-based phase-change absorbent system can effectively capture low-concentration CO 2 to produce kilogram-scale EDA-CA. • The yield achieved via the sequential strategy is enhanced by ∼4 times compared to employing EDA and pure CO 2 at 3 MPa. • Facet-engineered NR-CeO 2 featuring the highest density of FLPs achieves the best yields in the production of cyclic ureas. [ABSTRACT FROM AUTHOR]

In order to prepare thermoplastic polyimide (PI) resins with good comprehensive performances, the modification of thermoplastic polyetherimides (PEIs) by 1,4-bis(2,3-dicarboxyphenoxy)-2- tert -butylbenzene dianhydride (3,3′-TBHQDA) was systematically investigated. The PEI-a-x and PEI-b-x series of polyetherimides were synthesized by chemical imidization of the diamine monomer m -phenylenediamine (m -PDA) with different contents of 1,4-bis(3,4-dicarboxyphenoxy)-2- tert -butylbenzene dianhydride (4,4′-TBHQDA) and 3,3′-TBHQDA or 4,4′-(4,4′-isopropylidenediphenoxy) bis(phthalic anhydride) (4,4′-BPADA) and 3,3′-TBHQDA. These PEIs had glass transition temperatures (T g s) in the range of 217–264 °C, low melt viscosities of 79–2367 Pa s, good transmittances of 87–88 % at 450 nm, and displayed good mechanical properties with tensile modulus of 2.8–3.2 GPa, tensile strengths of 89.6–118.4 MPa, and elongations at break of 3.9–6.4 %. The introduction of 3,3′-TBHQDA successfully improved thermal properties and melt processability of the PEIs. Among them, PEI-a-50 and PEI-b-50 displayed better comprehensive performances in PEI-a-x and PEI-b-x series, respectively, with moderate T g s (256 and 249 °C, respectively), extremely low melt viscosities (161 and 297 Pa s at 400 °C, respectively), high transmittances at 450 nm (87 %), and good mechanical properties (tensile modulus of 3.1 and 2.8 GPa, tensile strengths of 105.6 and 106.3 MPa, respectively). [Display omitted] • The modification of PEIs based on 4,4′-TBHQDA and 4,4′-BPADA by 3,3′-TBHQDA. • The heat resistance and melt processability of PEIs were modified by 3,3′-TBHQDA. • The PEI-a-50 and PEI-b-50 showed T g s of 256 and 249 °C, respectively. • The PEI-a-50 and PEI-b-50 had melt viscosities of 161 and 297 Pa s, respectively. [ABSTRACT FROM AUTHOR]

In this electrochemical exploration, we scrutinized the influence of alkyl-diamine (AD) chain length as crucial linkers between glassy carbon electrodes (GCE) and citrate-capped gold nanoparticles (Cit-AuNPs), focusing on their conductive behavior and sensing proficiency, particularly in hydrazine detection. Meticulous examination of self-assembled monolayers (SAMs) formed by three distinct ADs, namely 1,6-hexanediamine (HDA), 1,8-octanediamine (ODA) and 1,10-decanediamine (DDA) unfolded over GC surfaces revealed a precise adherence to Langmuir adsorption kinetics during the SAM formation process. Utilizing cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), the electrochemical activity of the [Ru(NH₃)₆]³⁺/²⁺ redox pair at electrodes modified with ADs was investigated. The proposed mechanism involves a Michael-like nucleophilic addition process at the GC surface/diamine solution interface during the SAM formation. Analysis across various techniques underscored the compact nature of the DDA-formed SAM in comparison to HDA and ODA. Exploiting the free amine functional groups on the SAMs, the as-synthesized Cit-AuNPs were attached on the electrode surface and investigated comprehensively through CV, EIS, attenuated total reflection Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Remarkably, Cit-AuNPs attached DDA-SAM/GC electrode offered superior electro active surface area, establishing an advanced electrochemical platform for carcinogenic hydrazine determination. The DDA/Cit-AuNPs electrode demonstrated a linear determination range of 0.003–1 mM, limits of detection at 11 nM, and sensitivity of 1080 µA mM−1 cm−2. This study gives a complete picture of how AD chain lengths, SAM formation, Cit-AuNPs attachment, and electrocatalytic performance work together to make an advanced electrochemical sensing scaffold for environmental pollutants determination. [Display omitted] • SAMs of alkyldiamines of different chain lengths were attached on glassy carbon electrode. • The SAM formation on electrode surface follows Michael-like nucleophilic addition. • Decanediamine (DDA)-based SAM efficiently attached on electrode surface. • Highly populated Cit-AuNPs was observed on DDA due to longer chain length with greater surface area. • The DDA-based AuNPs electrode exhibited enhanced hydrazine sensing with the detection limit of 11 nM. [ABSTRACT FROM AUTHOR]

Flexible polyimide foams (PIFs) demonstrate a great potential for applications in the fields of thermal insulation, flame retardancy and irradiation tolerance. In this work, mechanically flexible PIFs with anisotropic pore structure were prepared by adopting the copolymerization strategy and microwave-assisted foaming process. The copolymerization reaction was conducted to synthesize polyester ammonium salt (PEAS) precursors using 3,3′,4,4′-benzophenone tetracarboxylic acid dianhydride (BTDA) as dianhydride, 4,4′-diaminodiphenyl ether (ODA) and 4,4′-diaminodiphenyl sulfone (DDS) as the copolymerized diamines; afterwards, PEAS powders with particle sizes ranging from 100 to 300 μm were obtained by drying, crushing and sieving treatments, which were used as the feedstock for "bottom-up" microwave-assisted foaming and thermal imidization process, thereby leading to the formation of PIFs with regular three-dimensional near-spherical pores in vertical direction (parallel to the pore growth direction) and the aligned ellipsoidal strip-like pore structure in horizontal direction. The directional growth of foam pores resulted in anisotropic mechanical flexibility and thermal insulation performance. Moreover, PIFs possessed excellent thermal stability and flame retardancy with the initial thermal degradation temperature higher than 545 °C and limited oxygen index up to 58.8%. The PIFs exhibited exceptional thermal insulation performance with thermal conductivity values ranging from 0.0276 to 0.0517 W/(m·K) between 25 and 300 °C. Additionally, the PIFs demonstrated excellent irradiation tolerance, with the mechanical and thermal stability retention rate being above 96% after the irradiation experiment (radiation dosage: 1.15 × 105 Gy) using 60Co source. Thus, lightweight PIFs with superior high temperature thermal insulation performance, flame retardancy and irradiation tolerance were successfully prepared, which showed potential applications in aerospace, medical and nuclear power sectors. [Display omitted] • PIFs were prepared by copolymerization and microwave-assisted foaming strategy. • The directional growth of foam pores endowed PIFs with anisotropic structure. • The mechanical and flame retardancy were enhanced by introducing DDS. • PIFs had excellent high temperature thermal insulation and irradiation tolerance. [ABSTRACT FROM AUTHOR]

An efficient imine-linkage simple chromogenic probe, BPDA, has been introduced to detect sarin gas mimic diethylchlorophosphate (DCP), with a nanomolar range detection limit. [Display omitted] • A symmetrical imine-linkage simple chromogenic probe, BPDA, has been introduced to detect DCP. • The detection limit of BDPA with DCP has been estimated in the nanomolar range. • A paper strips-based portable test kit experiment has been demonstrated for on-spot detection of DCP. • A smartphone-based methods has been executed for on-spot detection and quantification of DCP. The severe toxicity and easy availability of nerve agents have caused an increase in the need to develop effective methods for identifying these lethal substances. Among the traditional platforms employed for this kind of purpose, chromophore-based chemosensors have garnered a significant amount of attention. In this study, we have designed, prepared, and characterized (N1E,N4E)-N1,N4-bis((Z)-3-(4-(dimethylamino)phenyl) allylidene)benzene-1,4-diamine, BDPA , a simple chromogenic probe of symmetrical diimine, having the extreme capability to sensing diethylchlorophosphate (DCP), the mimic of chemical warfare agent sarin not only in solution but also in solid and vapor phases with highly selective and sensitive manner. In the presence of DCP, a remarkable color change from light yellow to blue is observed in pure acetonitrile solvent and also shows pink color in 10 % acetonitrile–water by the naked eye, comes back to its former state after the introduction of triethylamine (TEA) which is found to be five times recyclability by alternately adding DCP and TEA. The detection limit of BDPA with DCP has been estimated in the nanomolar range, and also, response time towards sarin surrogate DCP is withina few minutes (∼5–6 min.).To determine its practical usability, we have developed a portable test kit that uses paper strips to assess the capability of BDPA for in-situ recognition and measurement of DCP. A dipstick method has also been executed to recognize gaseous DCP within the stores of analogous hazardous analytes to prove the effectiveness of the sensor, BDPA. A smartphone-based readout novel technique, i.e., RGB analysis, has provided an innovative platform for the instant, on-site, visual identification and measurement of DCP in remote areas. The current work presented an incredible probe and method for conveniently and instantly detecting and quantifying sarin gas mimics in actual dangerous circumstances. [ABSTRACT FROM AUTHOR]

Putrescine (Butane-1,4-diamine) has been regarded as a vital marker of spoiling protein-rich foods, especially meat and seafood. The detection of putrescine in food is considered a convenient and powerful method for evaluating the degree of spoilage of protein-rich foods. Herein, a novel rhodol-based fluorescent probe RSMA (formyl-rhodol Schiff base with methoxyaniline) was developed to detect putrescine. RSMA exhibited excellent linearity (R2 = 0.9912) in the concentration range of 0–45 μM of putrescine with a detection limit as low as 0.45 μM. Although RSMA had moderate responses to some aliphatic diamines, the selectivity of RSMA for putrescine was one of the best reported in the literature so far. Moreover, RSMA was successfully fabricated to solid-state sensors for on-site detection of putrescine in shrimp, that demonstrated its application in monitoring food spoilage. [Display omitted] • A highly selective rhodol-based putrescine probe RSMA was synthesized. • RSMA exhibited excellent linearity to putrescine in 0–45 μM with LOD of 0.47 μM. • RSMA was successfully applied for on-site detection of putrescine in shrimp. [ABSTRACT FROM AUTHOR]

Water contamination by heavy metal pollutants is a global concern due to detrimental effects on the environment and human health. Regenerable, high-performance heavy metal sorbents are urgently demanded for improved water purification. Herein, we present an elegant strategy of interweaving metal–organic framework (MOF-808-ethylene diamine tetraacetic acid) and TEMPO-oxidized cellulose nanofibers (TCNF) to construct freeways in hybrid aerogels for rapid and efficient transport and capture of heavy metal ions. In this strategy, a postsynthetic ligand exchange approach is applied to introduce ordered and high-density accessible binding sites for metal ions. The prepared aerogels show excellent shapeability, ultralow density less than 0.005 g cm−3, and high hierarchical porosity of 99.82%. Furthermore, benefiting from the abundant chelating groups and accessible surface areas, these aerogels exhibit outstanding uptake capacity of 300 mg g−1 and rapid adsorption kinetics of 0.031 mg g−1 h−1 for Cu(II) ions, significantly better than conventional TCNF aerogels. The aerogels could be easily regenerated at least five cycles without greatly performance loss. These aerogels could effectively remove diverse heavy metal ions from complicated contaminated water. Thus, this work provides a novel method to synthesize environmental-friendly, regenerable, and high-performance adsorption materials for water remediation. • An ultralight and shapeable nanocellulose/metal-organic framework aerogel was developed. • MOF-808-EDTA was anchored on TCNF by H-bonding and metal-ligand coordination bonding. • The rapid and efficient transport and capture of Cu(II) ions was achieved. • The aerogels could be easily regenerated at least five cycles without greatly performance loss. [ABSTRACT FROM AUTHOR]

[Display omitted] meso -Arylporphyrin containing two external chelating 2,2 ' :6 ' ,2 ' -terpyridine fragments and its zinc complex were synthesized. The key step comprised the amide bond formation between the porphyrin diamine derivative and 4 ' -(4-carboxyphenyl)-2,2 ' :6 ' ,2 ' -terpyridine. The compounds obtained seem to be potent for photodynamic therapy and diagnosis. [ABSTRACT FROM AUTHOR]

Three mononuclear heteroleptic nickel complexes bearing the non-innocent o-aminobenzenethiolate (2-amnt) ligand and different diamine ligands, namely, [Ni(2-amnt)(o-phen)] (o-phen = o-phenylenediamine) (1), [Ni(2-amnt)(3,4-daba)] (3,4-daba = 3, 4-diamino benzoic acid) (2) and [Ni(2-amnt)(dmnt)] (dmnt = diaminomaleonitrile) (3), were synthesized and characterized. Complexes 1 – 3 are active homogeneous proton reduction electrocatalysts in dimethylformamide with trifluoroacetic acid as a proton source. All the three complexes are tested in light-driven hydrogen evolution reaction, indicating different catalytic efficiencies. Thus, although complex 3 indicates no catalytic action, both complexes 1 and 2 catalyze H 2 evolution in water-dimethylformamide solutions using fluorescein (Fl) as a photosensitizer. Complex 2 acts as a homogeneous catalyst reached 834 turnovers (TON); whereas 1, d espite being active in hydrogen evolution reaction (HER), decomposes to form nanomaterials. DFT calculations combined with electrochemical and spectroscopic data were employed to investigate the catalytic mechanism for H 2 formation as well as to unravel the key factors that influence the relative catalytic efficiencies. The proposed catalytic pathway involves ligand-based reduction and protonation steps followed by the formation of a nickel-hydride intermediate that reacts with a solution proton to generate H 2 via a very low energy transition state. [Display omitted] • Three heteroleptic Ni(II)-diamine-aminobenzethiolate complexes were synthesized. • They act as proton reduction electrocatalysts and light-driven catalysts. • Their catalytic efficiency depends on the nature of the ligands. • DFT and experimental data reveals the key factors of hydrogen evolution mechanism. [ABSTRACT FROM AUTHOR]

The development of sustainable methods is highly desirable in synthetic organic chemistry. In this regard, we report hydroxylamine hydrochloride mediated, one-pot synthesis of 1,3-diazaheterocycles using anthranilamide or o -phenylenediamine with amides via transamidation under solvent free condition at 120–140 °C for 8–14 h. This method proceeds smoothly under metal- and oxidant-free conditions exhibited broad substrate scope with reference to both diamines derivatives and amides, resulted in corresponding 4(3 H)-quinazolinone (3) and benzimidazoles (5 & 6) (∼47 examples) in good to excellent yield (56–96 %). As an efficient and environmentally friendly access to a broad range of 4(3 H)-quinazolinones and benzimidazoles and the synthetic utility of this method was demonstrated by gram-scale operation, achieved >90 % yield. [Display omitted] [ABSTRACT FROM AUTHOR]