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The main goal of this work was to elucidate the potential relevance of (radio)metal chelates of 99mTc and Re targeting Gquadruplex structures for the design of new tools for cancer theranostics. 99mTc provides the complexes with the ability to perform single-photon-emission computed tomography imaging studies, while the Re complexes should act as anticancer agents upon interaction with specific G4 DNA or RNA structures present in tumor tissues. Towards this goal, we have developed isostructural 99mTc(I) and Re(I) tricarbonyl complexes anchored by a pyrazolyl-diamine (Pz) chelator carrying a pendant pyridostatin (PDS) fragment as the G4-binding motif. The interaction of the PDF-Pz-Re (8) complex with different G4-forming oligonucleotides was studied by circular dichroism, fluorescence spectroscopy and FRET-melting assays. The results showed that the Re complex retained the ability to bind and stabilize G4-structures from different DNA or RNA sequences, namely those present on the SRC proto-oncogene and telomeric RNA (TERRA sequence). PDF-Pz-Re (8) showed low to moderate cytotoxicity in PC3 and MCF-7 cancer cell lines, as typically observed for G4-binders. Biodistribution studies of the congener PDF-Pz-99mTc (12) in normal mice showed that the complex undergoes a fast blood clearance with a predominant hepatobiliary excretion, pointing also for a high in vitro stability. [ABSTRACT FROM AUTHOR]

Cobalt complexes have previously been reported to exhibit high faradaic efficiency in reducing CO2 to CO. Herein, we synthesized capsule-like cobalt–polypyridine diamine complexes [Co(L1)](BF4)2 (1) and [Co(L2) (CH3CN)](BF4)2 (2) as catalysts for the electrocatalytic reduction of CO2. Under catalytic conditions, complexes 1 and 2 demonstrated the electrocatalytic reduction of CO2 to CO in the presence or absence of CH3OH as a proton source. Experimental and computational studies revealed that complexes 1 and 2 undergo two consecutive reversible one-electron reductions on the cobalt core, followed by the addition of CO2 to form a metallocarboxylate intermediate [CoII(L)–CO22−]0. This crucial reaction intermediate, which governs the catalytic cycle, was successfully detected using high resolution mass spectrometry (HRMS). In situ Fourier-transform infrared spectrometer (FTIR) analysis showed that methanol can enhance the rate of carbon–oxygen bond cleavage of the metallocarboxylate intermediate. DFT studies on [CoII(L)–CO22−]0 have suggested that the doubly reduced species attacks CO2 on the C atom through the dz2 orbital, while the interaction with CO2 is further stabilized by the π interaction between the metal dxz or dxz orbital with p orbitals on the O atoms. Further reductions generate a metal carbonyl intermediate [CoI(L)–CO]+, which ultimately releases CO. [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]

A tert‐butyl nitrite (TBN) promoted visible‐light‐induced one‐pot C−N cross coupling reaction of 3‐alkylidene‐2‐oxindoles with benzene‐1,2‐diamine was explored. Simultaneously, the indoline motif of 3‐alkylidene‐2‐oxindoles as well as 3‐ylidene oxindoles are regioselectively nitrated at the C‐6 position by in‐situ formed NO2 radical. (E)‐3‐(2‐(aryl)‐2‐oxoethylidene)oxindole and (E)‐3‐ylidene oxindole produce distinct nitrated diastereomeric coupling products, a phenomenon influenced by the steric bulk of the functional group. The experimental findings suggest the potential involvement of a radical pathway in this reaction. [ABSTRACT FROM AUTHOR]

The significant medicinal and pharmacological facts about chromenes (benzopyran) nucleus prompted us to focus on constructing unique chromenes with biological value. New chromene derivatives 2–15 were synthesized, and their antibacterial effectiveness was studied. The reaction of the 2-amino-4H-chromene derivative 1 with a variety of reagents such as acetic anhydride, formic acid, chloroacetyl chloride, cyclopentanone, ethyl acetoacetate, diethyl malonate, aldehydes, and isatin produced derivatives 2–13. Compound 1 was also treated with aromatic amines such as p-toluidine and/or benzene-1,4-diamine with formaldehyde, yielding derivatives 14 and 15, respectively; spectral techniques were used to confirm the predicted structures of all compounds. The antibacterial activity of the recently synthesized compounds was assessed against two types of bacteria, Bacillus subtilis and Escherichia coli. There is encouraging antibacterial activity in compounds 5 and 7. [ABSTRACT FROM AUTHOR]

Three new copper(II) complexes, [CuClL] (1), [CuBrL]n (2) and [CuL(NCS)]n (3), derived from the Schiff base 2,4-dichloro-6-((2-pyrrolidin-1-ylethylimino)methyl)phenol (HL) have been prepared and characterized by spectroscopic methods, as well as single crystal X-ray determination. The Cu atom in complex 1 is in square planar coordination, and those in complexes 2 and 3 are in square pyramidal coordination. The Schiff base ligand coordinates to the Cu atoms through phenolate oxygen, imino nitrogen and pyrrolidine nitrogen. The antibacterial activities of the Schiff base and the three copper complexes have been assayed on the bacteria Staphylococcus aureus and Escherichia coli and the yeast Candida parapsilosis. [ABSTRACT FROM AUTHOR]

The results of a study of the antifungal properties of an imidazoline hexyl bromide complex obtained on the basis of bicyclo[2.2.1]hept-5-ene-2-carboxylic acid and triethylenetetraamine as an additive to cutting fluids are presented. First, imidazoline was obtained by reacting norbornene carboxylic acid with triethylene tetraamine. In the next step, imidazoline was reacted with hexyl bromide to obtain its alkyl halide complex. The physicochemical properties of the resulting complex were determined, and its composition and structure were confirmed by IR spectroscopy. The complex has been tested as an antimicrobial additive in cutting fluids. It was found that the resulting complex has a destruction zone of 1.3-1.5 cm at a concentration of 0.25% and 2.4-2.6 cm at a concentration of 0.5%. N'-(2,2-bicyclo[2.2.1]hept-5-en-2-yl-4,5-dihydro-1-Himidazolin-1-ylethyl)ethane-1,2-diamine hexyl bromide complex as an antimicrobial additive exhibiting high fungicidal properties, destroys fungi even at a concentration of 0.25% - the affected area is 1.3-1.5 cm. [ABSTRACT FROM AUTHOR]

Objective: This article is focused on synthesis and characterisation of 1,1-(((5-(3,4,5triethoxybenzyl)pyrimidine-2,4-diyl))bis(azanediyl))bis(substituted phenyl methylene))bis(naphthalen-2-ol) moieties and evaluated for antibacterial and antioxidant activities as well as molecular docking and molecular dynamic simulation investigations. Methods: In this article we conducted one-pot three component reactions through Betti type reaction. Agar diffusion method was used to evaluate anti-bacterial properties. The DPPH method was used to determine antioxidant activity results. Results: A series of 1,1-(((5-(3,4,5triethoxybenzyl)-pyrimidine-2,4-diyl))bis(azanediyl))bis(substituted phenyl methylene))bis(naphthalen-2-ol) were synthesized via Betti type reaction and evaluated for their antibacterial and antioxidant activities. Further, all the synthesized compounds were characterized by FT-IR, 1H, and 13C NMR, and mass spectral analysis. Discussion: Molecular docking was carried out to study possible potential binding interaction of synthesized Betti base derivatives with 1NC6 PDB as receptor. The molecular dynamic (MD) was performed to investigate stability of binding interaction of drug-target (protein–ligand) complex. All the synthesized compounds were investigated for their antibacterial and antioxidant activity. Conclusions: Betti base derivatives were synthesized and studied on the basis of computer aided drug design including docking and molecular dynamic (MD) simulations and pharmacologically assessed for antioxidant and antibacterial activity. Molecular docking investigation revealed that compounds showed better binding energies in the range –4.1 to –7.3 kcal/mol suggests that the binding occurs efficiently in the receptor–ligand complex. These Betti base derivatives were synthesized via Betti base protocol at 70oC through one-pot three component reaction with acceptable yields, as cost efficient, high yield, easy workup and environmental friendliness. Afterwards, obtained molecules have characterized by FT-IR, NMR, and Mass spectra which confirms the chemical structure of the synthesized compounds. [ABSTRACT FROM AUTHOR]

A four-step synthesis process of bifunctional, noncovalent organocatalysts based on the chiral (1R,2R)-cyclohexane-1,2-diamine scaffold containing a 1,2-benzenediamine H-bond donor was developed. Nucleophilic aromatic substitution of the 2-fluoronitrobenzene derivative with the commercial (1R,2R)-cyclohexane-1,2-diamine was followed by selective alkylation of the primary amino group, reduction of the aromatic nitro group and final derivatization of the primary aromatic amino group, i.e., acylation, sulfonation, reductive alkylation and arylation, leading to the four subtypes of organocatalysts. All new compounds were fully characterized. The prepared organocatalysts (32 examples) were tested in the Michael addition of acetylacetone to trans-β-nitrostyrene, yielding the addition product with incomplete conversions (up to 93%) and enantioselectivities of up to 41% ee. [ABSTRACT FROM AUTHOR]

Dual microcapsule systems, especially those based on the polyurea matrix, have emerged as pivotal components driving innovation in self-healing materials, thanks to the intrinsic properties of polyurea, primarily diamine and diisocyanate, rendering it an optimal choice for enhancing self-healing coatings. However, the encapsulation of polyurea components is fraught with substantial technical hurdles. Addressing these challenges, a novel methodology has been devised, leveraging n-heptane as a solvent in the liquid diamine emulsion process to facilitate the synthesis of diamine microcapsules. These microcapsules exhibit a uniform spherical morphology and a robust shell structure, with an encapsulated core material ratio reaching 39.69%. Analogously, the encapsulation process for diisocyanate has been refined, achieving a core material percentage of 10.05 wt. %. The integration of this bifunctional microcapsule system into diverse polymeric matrices, including epoxy resins and polyurethanes, has been demonstrated to significantly enhance the self-healing efficacy of the resultant coatings. Empirical validation through a series of tests, encompassing scratch, abrasion, and saltwater immersion assays, has revealed self-healing efficiencies of 21.8% and 33.3%, respectively. These results indicate significant improvements in the durability and self-repair capability of coatings, marking a notable advancement in self-healing materials with promising potential for tailored applications in automotive, aerospace, and construction industries. [ABSTRACT FROM AUTHOR]

C22H20N2, orthorhombic, P212121 (no. 19), a = 13.4475(3) Å, b = 14.6000(3) Å, c = 17.3708(4) Å, V = 3,410.47(13) Å3, Z = 8, Rgt(F) = 0.0414, wRref(F2) = 0.1026, T = 173(2) K. [ABSTRACT FROM AUTHOR]

C22H20N2, orthorhombic, P212121 (no. 19), a = 13.4475(3) Å, b = 14.6000(3) Å, c = 17.3708(4) Å, V = 3,410.47(13) Å3, Z = 8, Rgt(F) = 0.0414, wRref(F2) = 0.1026, T = 173(2) K. [ABSTRACT FROM AUTHOR]

Diamine-appended Mg2(dobpdc) (dobpdc4- = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate) metal-organic frameworks are a promising class of CO2 adsorbents, although their stability to SO2─a trace component of industrially relevant exhaust streams─remains largely untested. Here, we investigate the impact of SO2 on the stability and CO2 capture performance of dmpn-Mg2(dobpdc) (dmpn = 2,2-dimethyl-1,3-propanediamine), a candidate material for carbon capture from coal flue gas. Using SO2 breakthrough experiments and CO2 isobar measurements, we find that the material retains 91% of its CO2 capacity after saturation with a wet simulated flue gas containing representative levels of CO2 and SO2, highlighting the robustness of this framework to SO2 under realistic CO2 capture conditions. Initial SO2 cycling experiments suggest dmpn-Mg2(dobpdc) may achieve a stable operating capacity in the presence of SO2 after initial passivation. Evaluation of several other diamine-Mg2(dobpdc) variants reveals that those with primary,primary (1°,1°) diamines, including dmpn-Mg2(dobpdc), are more robust to humid SO2 than those featuring primary,secondary (1°,2°) or primary,tertiary (1°,3°) diamines. Based on the solid-state 15N NMR spectra and density functional theory calculations, we find that under humid conditions, SO2 reacts with the metal-bound primary amine in 1°,2° and 1°,3° diamine-appended Mg2(dobpdc) to form a metal-bound bisulfite species that is charge balanced by a primary ammonium cation, thereby facilitating material degradation. In contrast, humid SO2 reacts with the free end of 1°,1° diamines to form ammonium bisulfite, leaving the metal-diamine bond intact. This structure-property relationship can be used to guide further optimization of these materials for CO2 capture applications.

The document is the contents list for the journal "Chemical Communications" published in 2024. It includes articles on various topics such as enantioselective C-H bond functionalization, fluorescent metal nanoclusters, thioesterases for chemoenzymatic synthesis, and more. The journal is published by The Royal Society of Chemistry, a leading chemistry community. The document provides a list of articles and authors, allowing library patrons to quickly identify relevant research topics. [Extracted from the article]

A photoredox-catalyzed unsymmetrical diamination of alkenes by using N-aminopyridinium salts and nitriles as the amination reagents has been developed. Various vicinal diamines were obtained in moderate to excellent yields under mild reaction conditions. Furthermore, this protocol could be applied in the late-stage modification of pharmaceuticals and natural products. Preliminary mechanistic studies suggested that this methodology may undergo a radical pathway followed by a Ritter-type reaction. [ABSTRACT FROM AUTHOR]

Au(III) bis(pyrrolide-imine) chelates are emerging as a class of versatile, efficacious metallodrug candidates. Here, we synthesised two enantiopure chiral ligands H2L1 and H2L2 (tetradentate cyclohexane-1,2-diamine-bridged bis(pyrrole-imine) derivatives). Metallation of the ligands with Au(III) afforded the chiral cationic complexes AuL1 and AuL2. The in vitro cytotoxicities of AuL1 and AuL2 determined in the NCI-60 single-dose drug screen were 56.5% and 89.1%, respectively. AuL1 was subsequently selected for a five-dose NCI-60 screen, attaining GI50, IC50, and LC50 values of 4.7, 9.3 and 39.8 μM, respectively. Hierarchical cluster analysis of the NCI-60 data indicated that the profile for AuL1 was similar to that of vinblastine sulfate, a microtubule-targeting vinca alkaloid. Reactions of AuL1 with glutathione (GSH) in vitro confirmed its susceptibility to reduction, Au(III) → Au(I), by intracellular thiols. Because human serum albumin (HSA) is responsible for transporting clinically deployed and investigational drugs, we studied the uptake of AuL1 and AuL2 by HSA to delineate how chirality impacts their protein-binding affinity. Steady-state fluorescence quenching data acquired on the native protein and data from site-specific probes showed that the compounds bind at sites close enough to Trp-214 (subdomain IIA) of HSA to quench the fluorophore. The bimolecular quenching rate constants, Kq, were ca. 102 times higher than the maximum diffusion-controlled collision constant of a biomolecule in water (1010 M−1 s−1), confirming that static fluorescence quenching was the dominant mechanism. The Stern–Volmer constants, KSV, were ∼104 M−1 at 37 °C, while the affinity constants, Ka (37 °C), measured ∼2.1 × 104 M−1 (AuL1) and ∼1.2 × 104 M−1 (AuL2) for enthalpy-driven ligand uptake targeting Sudlow's site I. Although far- and near-UV CD spectroscopy indicated that both complexes minimally perturb the secondary and tertiary structure of HSA, substantial shifts in the CD spectra were recorded for both protein-bound ligands. This study highlights the role of chirality in determining the cytotoxicity profiles and protein binding behaviour of enantiomeric Au(III) chelates. [ABSTRACT FROM AUTHOR]

The first crystal structure of an ortho‐lithium phosphinothioic amide complexed with tetramethylethylenediamine 12 is reported. The complex consists of a spirane in which the spiro‐lithium is N,N‐ and C,S‐chelated by the diamine and organophosphorus ligands, respectively. The analogous ortho anion 14 obtained by Sn(IV)/Li transmetallation in THF has also been synthesized. Nuclear magnetic resonance study of both anions showed that they exist as monomers in solution and are involved in dynamic processes including the restricted rotation around the P−N bond. 14 is converted at room temperature by nucleophilic cyclization to the dearomatized anion 15, which evolves after a few hours to the benzophosphindole sulfide 16. Density functional theory calculations supported the aggregation state in solution and were used to explore the conformational space of anion 12, the mechanism of ortho‐lithiation directed by P(X)−N (X=O, S) groups, and the mechanism of formation of 15. [ABSTRACT FROM AUTHOR]

In this paper, the influence of diamines on the intrinsic structure and molecular mobility of cellulosic complexes is discussed. Cellulose was pre-swollen by ethylenediamine then put in contact with a series of aliphatic diamines at a stoechiometric ratio. These materials were then characterized by Wide Angle X-Ray diffraction (WAXS) and solid-state 13 C NMR spectroscopy. It was observed by WAXS that diamines are able to swell cellulose along the (010) crystallographic plane and are able to modify unit cell angle γ of cellulose monoclinic structure. Moreover according to their periodicity, ordered- or disordered-phases structures were identified in such cellulosic complexes by Cross Polarization - Magic Angle Spinning (CP-MAS) 13 C NMR spectroscpy. Two-dimensional Wide-line Separation (2D WISE) and T 1 relaxation time 13 C NMR spectroscopy experiments showed that complexes do exhibit molecular motions between 23 and 90 ∘ C. Modulated Differential Scanning Calorymetry (MDSC) further showed the presence of two glass transition temperatures T g , which were attributed, in combination with the 13 C NMR spectroscopy observations through a multiscale approach, to relaxation motions internal to the diamines chemical structure and to the motion of cellulose–diamine planes respectively. [ABSTRACT FROM AUTHOR]

We have previously reported the first formal hydroamination of enamines for the synthesis of chiral 1,2‐diamines. Here, we describe: (i) the discovery, optimization, and substrate expansion of this reaction; (ii) a novel and straightforward protocol for the "click‐type" synthesis of enamines in quantitative yield utilizing sodium sulfate in a dual role as an ancillary and dehydrating agent without the need for workup or purification; (iii) the application of this methodology to the first enantioselective synthesis of orthogonally protected 1,1′‐(1‐(4‐fluorophenyl)ethane‐1,2‐diyl) piperazines, a scaffold for rapid lead optimization in drug discovery; (iv) a computational investigation into the mechanism and rationalization of the enantioselectivities of the reaction. [ABSTRACT FROM AUTHOR]

An asymmetric transfer hydrogenation of 2‐oxazolones in the presence of a chiral diamine ruthenium catalyst with potassium formate as a hydrogen source and potassium carbonate as an additive in 2,2,2‐trifluoroethanol is described. A series of chiral 2‐oxazolidinones were obtained with 29%–95% yields and 86%–>99% ee's. Furthermore, gram‐scale synthesis of chiral 2‐oxazolidinone and its downstream derivatizations demonstrate the practicality of this method. [ABSTRACT FROM AUTHOR]

Chiral aromatic alcohols with unique structures have attracted wide attention in asymmetric catalysis for decades. In this study, polymeric micelles with chiral diamine-Ru(II) catalysts in the hydrophobic core for asymmetric transfer hydrogenation of ketones affording chiral aromatic alcohols were presented. Firstly, block copolymers with (1R,2R)-(+)-1,2-diphenyl ethylenediamine (DPEN) in the pendant chain were successfully synthesized by Ring-Opening Metathesis Polymerization (ROMP) using 1,1-dimethyl ethyl N-(2-amino-1,2-diphenylethyl) carbamate (NB-DPEN-Boc) and polyethylene glycol (NB-PEG2000) with norbornene groups as raw materials. The structures of block copolymers P(DPEN)-co-P(PEG2000) were characterized by FT-IR and 1H NMR. Next, Block copolymers with chiral DPEN ligand in the pendant chain coordinate with [RuCl2(p-cymene)]2 to provide amphiphilic polymers with chiral diamine-Ru(II) catalyst. Then, the self-assembly of the amphiphilic polymers in water produced the polymeric micelles with chiral diamine-Ru(II) catalysts in the hydrophobic core. The particle sizes were found to be 65 nm by DLS analysis. The polymeric micelles as catalytic nanoreactors were successfully applied in the asymmetric transfer hydrogenation (ATH) of various ketones in water. The heterogenization of homogeneous catalysts and construction of catalysts for aqueous catalysis demonstrate potential application prospects in the preparation of chiral aromatic alcohols. [ABSTRACT FROM AUTHOR]

A vicinal diamine motif can be found in numerous natural compounds and pharmaceuticals, making it an important synthetic target. Herein, we report a telescoped synthesis of vicinal diamines under continuous flow conditions. This approach involves the electrochemical aziridination of alkenes with primary amines, followed by the strain-release driven ring-opening using various nitrogen nucleophiles. The efficacy of the developed method was demonstrated through the synthesis of diverse symmetrically and non-symmetrically substituted vicinal diamines, as well as vicinal amino azides, which can be further hydrogenated to diamines in flow. Additionally, O-centered nucleophiles were employed for the ring-opening of aziridines in our telescoped synthesis, yielding vicinal amino ethers and alcohol. This process offers a streamlined and efficient pathway for the direct synthesis of valuable products from readily available starting materials, bypassing the isolation of unstable aziridine intermediates. [ABSTRACT FROM AUTHOR]

Developing cross-linked polymers with both low dielectric constant and degradability for microelectronics and sustainability remains a challenge. Herein, a new fluoro-containing dialdehyde monomer (VF) derived from vanillin was synthesized, which was then cross-linked with a tris (2-aminoethyl) amine (TREN) and different diamines (4, 4′-methylenebis (cyclohexylamine) (PACM), 4, 4′-diaminodiphenylmethane (DDM) and 1, 6-hexamethylenediamine (HMDA)) to give three polyimines thermosets, namely VFT-P, VFT-D and VTF-H, respectively, showing controlled comprehensive properties through regulation of imine cross-linked structures. Properties-function relationship of these polyimines was systematically studied and focused mainly on revealing the degradation process and the mechanism of the degradability of polyimines. The results indicated that among these polyimines, VFT-P exhibited superior conventional properties and acid resistance due to its appropriate reactivity, cross-linked density, rigid non-conjugated Schiff base structures, and high free volume. The storage modulus, glass transition temperature, transmittance, and tensile strength of VFT-P polyimines could reach 3.40 GPa, 134 °C, > 97% (at 500–800 nm) and 62.47 ± 3.65 MPa, respectively. Besides, a low dielectric constant of 2.96 at 100 MHz and superior degradability was achieved. This study introduces a facile and effective design strategy to achieve the compatibility of target properties and also offers a potentially sustainable alternative to conventional cross-linked dielectric polymers. [ABSTRACT FROM AUTHOR]

The imidazolidine derivatives were prepared via [1 + 1] condensation of various aldehydes such as 2-Hydroxy benzaldehyde, 2-fluoro benzaldehyde, 2-chloro benzaldehyde, pyridine-2-carbaldehyde, pyrrole-2-carbaldehyde, thiophene-2-carbaldehyde, furan-2-carbaldehyde with N,N′-bis((pyridine-2-yl)methyl)ethane-1,2-diamine (L) in the solvent of acetonitrile and characterized by the appropriate spectroscopic methods (FT-IR, UV–Vis, molar conductivity, 1H and 13C NMR, EI-Mass, X-ray). By coordinating the imidazolidine ring to the metal ions, this ring can be stabilized or hydrolyzed and converted to initial materials. Therefore, in this research, to investigate the effect of imidazolidine ring pressure and the effect of different groups in neutralizing this pressure in coordination with manganese(II) ion, the Manganese(II) complexes of these compounds were synthesized and characterized by FT-IR, UV–Vis spectroscopy, molar conductivity, EI-Mass spectrometry, and X-ray crystallography. The spectroscopic data for the imidazolidine derivatives confirm their formation. The manganese(II) complex of these compounds showed that the imidazolidine ring was unstable due to coordinated and created pressure on the imidazolidine ring and the presence of different groups on the ring does not affect the stability. [ABSTRACT FROM AUTHOR]

In this study, various diamine monomers were used to synthesize aramid polymer films via a low-temperature solution condensation reaction with diacid chloride. For diamines with relatively high basicity, the reaction system became opaque because amine salt formation inhibited polymer synthesis. Meanwhile, low-basicity diamines with strong electron-withdrawing groups, such as CF3 and sulfone, were smoothly polymerized without amine salt formation to provide highly viscous solutions. The acid byproduct HCl generated during polymerization was removed by adding propylene oxide to the reaction vessel and converting the acid into highly volatile inert substances. The resulting solutions were used as varnishes without any additional purification, and polymer films with an excellent appearance were easily obtained through a conventional casting and convection drying process. The films neither tore nor broke when pulled or bent by hand; furthermore, even when heated up to 400 °C, they did not decompose or melt. Moreover, polymers prepared from 2,2-bis(trifluoromethyl)benzidine (TFMB) and bis(4-aminophenyl)sulfone (pAPS) did not exhibit glass transition until decomposition. The prepared polymer films showed a high elastic modulus of more than 4.1 GPa and a high tensile strength of more than 52 MPa. In particular, TFMB-, pAPS-, and 2,2-bis(4-aminophenyl)hexafluoropropane-based polymer films were colorless and transparent, with very high light transmittances of 95%, 96%, and 91%, respectively, at 420 nm and low yellow indexes of 2.4, 1.9, and 4.3, respectively. [ABSTRACT FROM AUTHOR]

Ten mixed‐ligand phenyl mercury(II) complexes containing 1‐methyl‐1H‐tetrazole‐5‐thiol (HmtzS) (1) and phosphine or amine ligands. These complexes fall into two groups: [PhHg(mtzS){Ph2P(CH2)PPh2}]2 (2) and [PhHg(mtzS){Ph2P(CH2)nPPh2}] (3‐6), where n varies, and [PhHg(mtzS)(diamine)] (8‐10), with diamine choices being 2,2′‐bipyridyl (Bipy, 8), 1,10‐phenathroline (Phen, 9), or ethylenediamine (en, 10). These complexes were synthesized with moderate to high yields and characterized using various techniques. Characterization data revealed that the mtzS− ligand coordinates as a monodentate ligand through the thiolate sulfur atom in all complexes, adopting a tetrahedral geometry around the Hg(II) center. Furthermore, complexes [PhHg(mtzS)] (1) and its diamine derivatives (8‐10) were assessed for hydrogen storage at 77 K using the VTI method. Results demonstrated that the incorporation of diamines improves hydrogen storage capacity at low pressure. The precursor stored (1) 2.3 wt.% at 80 bar, while the other complexes showed storage capacities ranging from 2.9 to 3.86 wt.% at pressures of 45‐60 bar. Thermodynamic properties of the [PhHg(mtzS)(Bipy)] complex was calculated at three different temperatures. The results prove that the entropy was equal to 0.50543599 J/mol H2. K while the enthalpy equal to 0.0942638 KJ/(mol H2). [ABSTRACT FROM AUTHOR]

Diiminic Schiff bases (DSBs) were proven to be an intriguing candidate for coinage metal-enhanced fluorescence (MEF). DSBs were synthesized via the condensation reaction of salicylaldehyde (SL) and diamines. Silver and copper nanoparticles (synthesized in situ with the reaction of SL) showed significant enhancement of fluorescence selectively depending on the experimental conditions. SL was oxidized to its quinone form, while Ag+ or Cu2+ was reduced to its zero-valent state at the alkaline condition. DSBs acted as reducing as well as stabilizing agents. By changing diamines, the distance between two iminic bonds was manipulated and different extents of MEF were obtained. Detection of highly toxic metal ions is a challenge in an aqueous system in the context of water pollution. Ionic mercury, copper, and silver (released from natural as well as anthropogenic activities) were sensed selectively using turn-on/off fluorescence with a significant limit of detections involving DSBs-induced MEF. Biological compounds are found in remarkable quantities in natural water, creating a long-lasting effect on the food chain and ecology. Cysteine and dopamine were also sensed via the quenching of DSBs-stimulated MEF. Here, we summarized the toxicity of water pollutants and intriguing role of DSBs in coinage MEF for the decontamination of water with plausible mechanism. Such MEF sensed a series of inorganic and biological emerging pollutants in the water system selectively and sensitively. Imine-induced selectivity and manipulation of experimental conditions help to design intriguing sensing platform for the detection of water pollutants. [ABSTRACT FROM AUTHOR]

Developing luminescent materials that exhibit strong emissions in both solution and solid phases is highly desirable and challenging. Herein, we report imine‐bond directed formation of a rigid organic cage (TPE‐cage) that was synthesized by [2+4] imine condensation of a TPE‐cored tetra‐aldehyde (TPE‐TA) with a clip‐like diamine (XA) to illustrate confinement‐induced fluorescence enhancement. Compared to the non‐emissive TPE‐TA (ϕF=0.26 %) in the dichloromethane (DCM) solution, the TPE‐cage achieved a remarkable (~520‐fold) emission enhancement (ϕF=70.38 %). In contrast, a monomeric tetra‐imine model compound (TPE‐model) showed only a minor enhancement (ϕF=0.56 %) in emission compared to the parent tetra‐aldehyde TPE‐TA. The emission of TPE‐cage was further enhanced by ~1.5‐fold (ϕF=80.96 %) in the aggregated state owing to aggregation‐induced emission enhancement (AIEE). This approach establishes the potential for synthesizing luminescent materials with high emission in both solution and solid‐state by employing a single‐step imine condensation reaction. [ABSTRACT FROM AUTHOR]

Reactions involving Zintl ions are typically carried out in N‐based solvents such as liquid ammonia (NH3(l)), ethane‐1,2‐diamine (en), pyridine (py), or acetonitrile (CH3CN). We are currently investigating the application of other solvents as alternatives. Herein, we present the synthesis of the (Sn4Bi4)2− anion, obtained as its [K(crypt‐222)]+ salt (crypt‐222=4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane), from reactions of the binary, pseudo‐tetrahedral Zintl anion (Sn2Bi2)2− in the presence of phosphines as oxidation agents in ortho‐difluorobenzene (o‐DFB). The cluster comprises 38 valence electrons, hence, represents an arachno‐type architecture according to Wade‐Mingos rules. Micro‐X‐ray fluorescence (μ‐XFS) spectroscopy rationalized the elemental composition of the anion, and quantum chemical studies served to compare the stability of possible structural isomers of the global minimum structure. [ABSTRACT FROM AUTHOR]

Salen-based octahedral trans metallo-salen complexes with monodentate co-ligands may exist as several conformational isomers, including stepped and umbrella shaped conformations. However, the factors governing the selective isolation of a particular conformer have not been investigated properly. In this report, six mononuclear cobalt(III) complexes (1–6) with a tetradentate salen-type Schiff base ligand, N,N′-bis(3-methoxy-5-methylsalicylidene)-ethane-1,2-diamine (H2L), and different heteroaromatic co-ligands (pyridines, imidazole and pyrazole) have been synthesized and characterized to unveil the influence of heteroaromatic co-ligands on the conformational (stepped versus umbrella) selectivity of the resulting complexes. X-ray crystallography reveals that the structures of 1–6 are eventually similar with only differences in the coordinated heteroaromatic moieties at axial positions and the accommodation of a different number of lattice solvent/guest molecules in the crystal voids. Interestingly, although a landscape of intermolecular non-covalent interactions are present in the solid state in these systems, the pyridyl co-ligands exclusively stabilize the umbrella-shaped conformation, while five-membered heteroaromatic bases prefer the stepped-shaped conformation, disclosing that the different degrees of intramolecular interactions (repulsion/attraction) of the six and five membered heteroaromatic ligands at the axial positions play the most important role in the selective stability of the different conformations in the solid state. All these complexes exhibit efficient catalytic activity mimicking the functions of phenoxazinone synthase and catechol oxidase. The catalyst recyclability test was also performed and it showed a very negligible change in catalytic efficiency even after five catalytic cycles. Theoretical calculations were performed to gain in-depth understanding of the preference of pyridine ligands for the umbrella-shaped conformation and the five-membered ring co-ligands for the stepped-shaped one, as well as for the mechanistic investigation of the aerobic oxidation of o-aminophenol in the presence of 1–6 as catalysts. [ABSTRACT FROM AUTHOR]

Many efforts have been made in the last few decades to selectively transport antitumor agents to their potential target sites with the aim to improve efficacy and selectivity. Indeed, this aspect could greatly improve the beneficial effects of a specific anticancer agent especially in the case of orphan tumors like the triple negative breast cancer. A possible strategy relies on utilizing a protective leaving group like alizarin as the Pt(II) ligand to reduce the deactivation processes of the pharmacophore enacted by Pt resistant cancer cells. In this study a new series of neutral mixed-ligand Pt(II) complexes bearing alizarin and a variety of diamine ligands were synthesized and spectroscopically characterized by FT-IR, NMR and UV–Vis analyses. Three Pt(II) compounds, i.e., 2b, 6b and 7b, emerging as different both in terms of structural properties and cytotoxic effects (not effective, 10.49 ± 1.21 μM and 24.5 ± 1.5 μM, respectively), were chosen for a deeper investigation of the ability of alizarin to work as a selective carrier. The study comprises the in vitro cytotoxicity evaluation against triple negative breast cancer cell lines and ESI-MS interaction studies relative to the reaction of the selected Pt(II) complexes with model proteins and DNA fragments, mimicking potential biological targets. The results allow us to suggest the use of complex 6b as a prospective anticancer agent worthy of further investigations. [ABSTRACT FROM AUTHOR]

Reactions involving Zintl ions are typically carried out in N‐based solvents such as liquid ammonia (NH3(l)), ethane‐1,2‐diamine (en), pyridine (py), or acetonitrile (CH3CN). We are currently investigating the application of other solvents as alternatives. Herein, we present the synthesis of the (Sn4Bi4)2− anion, obtained as its [K(crypt‐222)]+ salt (crypt‐222=4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane), from reactions of the binary, pseudo‐tetrahedral Zintl anion (Sn2Bi2)2− in the presence of phosphines as oxidation agents in ortho‐difluorobenzene (o‐DFB). The cluster comprises 38 valence electrons, hence, represents an arachno‐type architecture according to Wade‐Mingos rules. Micro‐X‐ray fluorescence (μ‐XFS) spectroscopy rationalized the elemental composition of the anion, and quantum chemical studies served to compare the stability of possible structural isomers of the global minimum structure. [ABSTRACT FROM AUTHOR]

A novel method for synthesizing biobased diamide tetraol derivatives through mechanochemical processes is presented in this study. The key component used in the synthesis is (S)-γ-hydroxymethyl-γ-butyrolactone (2H-HBO), a cellulose-based lactone derived from levoglucosenone, combined with various linear diamines. The use of planetary ball milling in the presence of a small excess of diamine was found to be crucial for achieving complete conversion of 2H-HBO and the selective formation of diamide tetraol derivatives. The optimized parameters established for the reaction of 2H-HBO using diaminohexane were applied to biobased, non-toxic, and biodegradable diamines such as spermidine, spermine, and 4,9-dioxa-dodecanediamine. This resulted in high conversions and good yields of diamide tetraol derivatives. The scalability of the process was demonstrated by transposing the reaction from 100 mg to 2 g, with improved conversions obtained at a larger scale. The greenness of the procedure was assessed using the E-factor and EcoScale, showing low waste generation and acceptable to excellent reaction conditions. In addition, enzymatic polymerization of diamide tetraol derivatives using CAL-B (Candida antarctica lipase B) as a biocatalyst was explored. Successful polymerization of monomers obtained from hexamethylene diamine and 4,9-dioxa-dodecandiamine was achieved, providing insights into the effect of enzyme loading and monomer ratios on the molecular weight of the resulting polymers. Despite challenges with certain monomers containing amine groups, this work offers a promising approach for producing multifunctional biobased polymers. [ABSTRACT FROM AUTHOR]

The hydrodeoxygenation (HDO) of renewable fats or fatty acids into alkanes is a powerful measure to address energy and environmental crises. Molybdenum carbide-based catalysts are promising due to their platinum-like noble metal electronic properties. In this paper, Mo2C catalysts were prepared by one-step carbonization of amine molybdenum oxide (AMO) precursors using diamines with different carbon chain lengths as ligands. The physical and chemical properties and the HDO catalytic activity of the catalysts were investigated. The results indicate that as the carbon chain of diamines in the precursor increases, the carbon content of the catalysts in the surface and bulk phase increases. The Mo2C-12 catalyst exhibited excellent catalytic performance, with a palmitic acid conversion rate of 100% and an alkane selectivity of 96.6%, which are attributed to the smallest particle size, largest pore size, and synergistic effect of carbon. This work provides a simple and safe method for regulating the surface properties of Mo2C catalysts. [ABSTRACT FROM AUTHOR]

An efficient, one-pot quantitative procedure for the preparation of benzo[a]pyrano[2,3-c]phenazine derivatives from four-component condensation reaction of 2-hydroxynaphthalene-1,4-dione, benzene-1,2-diamine, aromatic aldehydes, and malononitrile in the presence of [(EtO)3Si(CH2)3N+H3][CH3COO−] as basic ionic liquid as catalyst in homogenous solution under solvent-free conditions at 90 °C is described. Simple procedure, high yields, short reaction times, and an environmentally benign method are advantages of this protocol. The [(EtO)3Si(CH2)3N+H3][CH3COO−] can be recovered and reused several times without loss of its activity. [ABSTRACT FROM AUTHOR]

Background: Inflammation and metabolic disorders are important factors in the occurrence and development of obesity complications. In this study, we investigated the protective effect and underlying mechanism of a novel pyrimidine-2,4-diamine derivative, Cyy-287, on mice fed a high-fat diet (HFD). Methods: The mice were randomly separated into four groups (n = 7): control (regular diet), HFD, HFD with Cyy-287 (5 mg/kg), and HFD with Cyy-287 (20 mg/kg) following HFD feeding for 10 weeks. After a 10-week administration, ALT and AST enzymes, echocardiography, immunohistochemical (IHC), Western blot (WB), Masson and Sirius Red staining were used to evaluate functional and morphological changes to the heart and liver. Microsomes from the mouse liver were extracted to quantify the total amount of CYP450 enzymes after drug treatment. Results: Cyy-287 decreased the levels of serum glucose, LDL, TC, ALT, and AST activities in HFD-treated mice. However, Cyy-287 administration increased ejection fraction (EF) and fractional shortening (FS) index of the heart. Cyy-287 inhibited histopathological changes in the heart and liver; decreased inflammatory activity; significantly diminished p38 mitogen-activated protein kinase (MAPK), the nuclear factor-kappa B (NF-κB) axis, and sterol regulatory element-binding protein-1c (SREBP-1c); and upregulated the AMP-activated protein kinase (AMPK) pathway in HFD-treated mice. Cyy-287 restored the content of hepatic CYP450 enzymes. Conclusion: These findings demonstrated that Cyy-287 protected heart and liver cells from obesity-induced damage by inhibiting inflammation, fibrosis, and lipid synthesis. [ABSTRACT FROM AUTHOR]

Using di-2-furanylethanedione and 5-bromo-3-methylbenzene-1,2-diamine we prepared a monomeric [MoO2(SL)] with a Schiff base, as well as 4 different compounds using the formulation [MoO2(MSL). We investigate how [MoO2(SL)] reacts with 1,3-diketones. Several characterizations are discussed in this article, including molar conductance measurement, elemental analysis, UVVis, IR, NMR, and thermal measurements. Molybdenum has a six-coordination number. All five MoO2(VI) compounds have distorted octahedral arrangements. Molybdenum octahedra have four N-atoms and two oxidized O-atoms.Against S. aureus and S. typhi, all synthesized compounds showed moderate activity. The chelation hypothesis is used to define the progression of the antibacterial task. [ABSTRACT FROM AUTHOR]

The use of 2,5‐diformylpyrrole in self‐assembly reactions with diamines and Zn(II)/Cd(II) salts allowed the preparation of [2]catenane, trefoil knot, and Borromean rings. The intrinsically dynamic nature of the diiminopyrrole motif rendered all of the formed assemblies intramolecularly flexible. The presence of diiminopyrrole revealed new coordination motifs and influenced the host–guest chemistry of the systems, as illustrated by hexafluorophosphate encapsulation by Borromean rings. [ABSTRACT FROM AUTHOR]

Transmetalation plays a very important role in the study of functional MOFs, but it is rarely used in metal–organic salts (MOSs). In this paper, four kinds of MOSs were synthesized by using the tetradentate ligand N,N′-bis (pyridin-4-ylmethyl) ethane-1,2-diamine and MCl2 (M = Zn, Co, Cu), labelled as [H4L]4+·2[CoCl4]2−·2H2O (1), [H4L]4+·2[ZnCl4]2−·2H2O (2), [H4L]4+·[CuCl4]2−·2Cl− (3), and [H4L]4+·2[CuCl4(H2O)]2− (4). Salt 3 was obtained by the metal-ion exchange of salt 1, and salt 4 was successfully synthesized by liquid-assisted grinding (LAG) of salt 3 and CuCl2·2H2O, which was a stoichiometric ratio-controlled transformation that occurred with the change in the geometry of copper(II) anions from [CuCl4]2− and [CuCl4(H2O)]2−. The reaction process was monitored dynamically by atomic absorption spectroscopy (AAS), fluorescence spectroscopy, and powder X-ray diffraction (PXRD). This suggested that transmetalation combined with LAG was an alternative method to obtain MOSs for different metal ions. [ABSTRACT FROM AUTHOR]

Solvent‐based CO2 capture consumes significant amounts of energy for solvent regeneration. To improve energy efficiency, this study investigates CO2 fixation in a solid form through solvation, followed by ionic self‐assembly‐aided precipitation. Based on the hypothesis that CO32− ions may bind with monovalent metal ions, we introduced Na+ into an aqueous hexane‐1,6‐diamine solution where CO2 forms carbamate and bicarbonate. Then, Na+ ions in the solvent act as a seed for ionic self‐assembly with diamine carbamate to form an intermediate ionic complex. The recurring chemical reactions lead to the formation of an ionic solid from a mixture of organic carbamate/carbonate and inorganic sodium bicarbonate (NaHCO3), which can be easily removed from the aqueous solvent through sedimentation or centrifugation and heated to release the captured CO2. Mild‐temperature heating of the solids at 80–150 °C causes decomposition of the solid CO2‐diamine‐Na molecular aggregates and discharge of CO2. This sorbent regeneration process requires 6.5–8.6 GJ/t CO2. It was also found that the organic carbamate/carbonate solid, without NaHCO3, contains a significant amount of CO2, up to 6.2 mmol CO2/g‐sorbent, requiring as low as 2.9–5.8 GJ/t CO2. Molecular dynamic simulations support the hypothesis of using Na+ to form relatively less stable, yet sufficiently solid, complexes for the least energy‐intensive recovery of diamine solvents compared to bivalent carbonate–forming ions. [ABSTRACT FROM AUTHOR]

The formation and follow‐up chemistry of P73− has been intensely studied in the recent decades. In contrast, corresponding investigations of its heavier polycyclic polypnictide congeners Pn73− (Pn=As, Sb, Bi), especially Bi73−, have been done to a much lesser extent. In our report, we add to these rare studies, by reporting new coordination compounds with As73− and Bi73−, respectively. Addition of PbI2 to a solution of K3As7 in ethane‐1,2‐diamine (en) afforded the heterometallic cluster anion [(As7)Pb(As7)]4− (with an 8 % co‐crystallization of [PbAs15]3− on the same site), in compound [K3.92(crypt‐222)4][(As7)Pb(As7)]0.92[PbAs15]0.08 ⋅ 3en (1). A similar reaction of [ZnPh2] with a pyridine (py) solution of the ternary solid 'K5Ga2Bi4', which was previously shown to release Ga and polybismuthide units in situ under certain reaction conditions, resulted in the formation of [K(crypt‐222)]4[(Bi7)Zn(Bi7)] ⋅ 2.5py (2), comprising the related heterometallic anion [(Bi7)Zn(Bi7)]4−. The former represents the first Pb−As binary Zintl anions obtained via solution chemistry, and the latter adds one more piece to the remarkably rare coordination compounds reported for Bi73−. [ABSTRACT FROM AUTHOR]

An approach to gem‐difluoro‐3‐azabicyclo[3.n.1]alkane‐ derived building blocks through double‐Mannich addition– deoxofluorination sequence is described. The scope of the method was demonstrated for a series of saturated (hetero)cyclic ketones or ketoesters (including five‐ to seven‐membered cycloalkane derivatives and N‐, O‐, S‐containing saturated heterocycles). Further transformations of functional groups produced various bifunctionalized difluorinated building blocks, namely, N‐protected aminoacids, mono‐N‐Boc‐protected diamines, and unprotected aminoalcohols in good to excellent overall yields. For the azabicyclo[3.3.1]alkane series, a potential for isosteric replacements is demonstrated by evaluation of the key physicochemical properties (i. e., pKa(H) and LogP). [ABSTRACT FROM AUTHOR]

The triazolate-assisted asymmetric dinuclear oxovanadium(IV) citrate [V2O2(cit)(Hdatrz)3]·5H2O (1, H4cit = citric acid, Hdatrz = 1H-1,2,4-triazole-3,5-diamine) and its additive salt [V2O2(cit)(Hdatrz)3][V2O2(cit)2]½·2H2datrz·9.5H2O (2) and the polymerized hexanuclear product [V6O6(μ3-O)2(cit)2(Hdatrz)4]·4H2O (3) have been isolated at different temperatures, respectively. Adduct 2 shows strong evidence for the conversion of a symmetric dinuclear oxovanadium(IV) citrate to a mixed-ligand asymmetric oxovanadium(IV) citrate. Moreover, a fully oxidized trinuclear vanadium(V) species [V3O6(μ2-OH)(μ3-O)(Hdatrz)2]·4.5H2O (4) has also been isolated as a quasi-intermediate product of 3 without the coordination of citrate. Intriguingly, an octanuclear mixed-valence oxovanadium(V / IV) citrate K2{[V IV/V2 O2(cit)(Hdatrz)(datrz)]2[V IV2 O2(cit)(Hdatrz)(datrz)]2}·27.5H2O (5) has been obtained with different vanadium units, where dinuclear mixed-ligands and mixed-valence oxovanadium(IV / V) citrates [V IV/V2 O2(cit)(Hdatrz)(datrz)] (5a) and [V IV2 O2(cit)(Hdatrz)(datrz)] (5b) have been trapped. Citrate adopts a μ2-η1:η1:η1:η2 coordination mode in 1, 2 and 5, while a μ3-η1:η1:η1:η2 fashion has been observed in 3. Unlike 1–4, complex 5 contains both protonated and deprotonated triazolates simultaneously, where four triazolates further coordinate in a μ3-η1:η1:η1 manner to construct an octanuclear unit. These different structural features in 1–5 are dominated by flexible multidentate citrates and protonated/deprotonated triazolates, showing their synergistic effects. Furthermore, 1 exhibits a rectangular channel, showing preferential adsorption of O2 and CO2 over gases N2, H2, and CH4. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Green Chemistry," published by The Royal Society of Chemistry. It highlights various articles and papers featured in the journal's latest issue, covering topics such as sustainable chemistry, electrocatalysis, and environmentally friendly synthesis methods. The journal aims to promote research for a greener and more sustainable future. [Extracted from the article]

2,3-Diamines are skeleton structures widely found in natural products and drug molecules and can also be used as ligands in transition metal catalysis. A novel visible light-driven synthesis method for 2,3-diamines using anilines and diisopropylethylamine as starting materials and aldehydes as proton acceptors under the action of the organic photosensitiser 4CzIPN has been developed. The method has mild conditions, avoids the use of metal reagents and the reaction mechanism does not involve the imine intermediate. Under optimal conditions, the yield of 2,3-diamines is up to 90%. In addition, the aldehydes give rise to 2,3-diols after the reaction, which means that the method can synthesise diamines and diols in one pot. [ABSTRACT FROM AUTHOR]

The N-formylation and N-methylation of amines with carbon dioxide (CO2) are important types of transformations which give access to a wide range of key intermediates and compounds. Efficient catalytic methods for both reactions are rare because of the challenge of controlling selectivity. Herein, we report the environmentally benign organocatalyzed N-formylation and N-methylation of primary and secondary amines using CO2 as the C1 source in the presence of hydrosilanes as the reductant. Readily available methyltriphenylphosphonium methylcarbonate has been proven to be an efficient catalyst for the N-methylation of amines and CO2 in the presence of polymethylhydrosiloxane (PMHS) under mild conditions. In contrast, the selective N-formylation is achieved in the presence of trimethoxysilane as the reductant. In both transformations, a wide range of substrates were selectively converted. 15 primary and secondary amines were N-methylated and N-formylated and the corresponding products were obtained in yields of up to 98% and 94%, respectively. Moreover, benzimidazoles are accessible from diamines and CO2 in a one-pot reaction in yields of up to 83%. Mechanistic investigations revealed different reaction pathways for N-methylation and N-formylation depending on the reductant as well as the activation of CO2 by the catalyst. [ABSTRACT FROM AUTHOR]

The novel complexes Sn(II), were synthesized of macrocyclic ligands derived from various diamine and dicarboxylic acids in the ratio of 2:2 and characterized by elemental analysis, molar conductance measurements, mass, NMR, FT-IR, and electronic spectra. The interactions of macrocyclic ligands (MLn) with SnCl2 in a 1:1 molar ratio in methanol produced the ensuing physiologically active [Sn(MLn)Cl2] type complexes, where n = 1 or 2. The complexes were initially identified using conductivity tests, molecular weight calculations, and elemental investigations. The bonding mode was determined using spectral data from the IR, 1H NMR, and 119Sn NMR. The complexes exhibit hexacoordinated octahedral geometry. The positive findings of Brine shrimp lethality of the ligands and their complexes have been discussed. The antimicrobial effects of each complex on several types of harmful fungus and bacteria have been assessed. The research focused on investigating and analyzing various aspects related to male fertility. It specifically investigated cauda epididymal spermatozoa density, sperm motility, testicular sperm density, fertility, and biological constraints of propagative tissues. The findings and discussions about these factors were presented in the study. [ABSTRACT FROM AUTHOR]

A series of environmentally friendly non-isocyanate polyurethanes (NIPUs) was synthesized through a polycondensation reaction of as-synthesized semi-bio-based bis-cyclic carbonate with diamine derivatives. The synthesis of biscyclic carbonate was realized, for the first time, from 1-thioglycerol and polyethylene glycol diacrylate via thiol-ene click and transcarbonation reaction, respectively. The impacts of using different diamine derivatives on the chemical structural, mechanical properties, thermal stability, and surface wettability of the NIPUs were determined. It was found that the NIPU containing fatty acid-based diamine decomposed at a lower temperature than that of other polymers. Besides, it demonstrated a lower Young’s modulus and a higher tensile strain at break, possibly due to its four-branched structure and greater flexibility. Meanwhile, the NIPU prepared with p-xylylenediamine provided the highest decomposition temperature, owing to an aromatic moiety in the polymer’s backbone, which improved its stiffness and thermal stability. Furthermore, it was understood that the NIPU containing diamino-N-methyldipropyl-amine exhibited a higher Young’s modulus and a lower tensile strain at break, as it had a nitrogen atom in its structure and a trigonal pyramidal configuration with the highest density of hydrogen bonds between polymer chains. Most of the developed NIPUs displayed hydrophobic surface properties, offering promising alternatives to isocyanate-based coating materials. [ABSTRACT FROM AUTHOR]

This work reports on the synthesis of non-isocyanate polyurethanes (NIPUs) obtained via the polyaddition of diamines: dimer fatty acid-derived diamine (DFA diamine) or polyether diamine (PPO diamine) with five-membered tri(cyclic carbonate) by a pre-polymerization method. The obtained NIPUs were further chemically modified by polyhedral oligomeric silsesquioxane (POSS) – glycidylisobutyl POSS (1epPOSS). The resulting reinforced composites, containing 5, 10 or 15 wt% 1epPOSS, were characterized in terms of their structure (FTIR, NMR, XRD), microstructure (SEM-EDS) and thermo-mechanical properties (DMA). FTIR confirmed the formation of polyurethanes, and NMR proved the chemical incorporation of 1epPOSS. XRD and SEM-EDS showed a uniform distribution of 1epPOSS in the matrix for low 1epPOSS concentration, with some agglomeration effects depending on the concentration of 1epPOSS. DMA indicated mechanical reinforcement of NIPUs based on DFA diamine. For NIPUs synthesized with PPO diamine, the composite with the highest 1epPOSS loading (15 wt%) exhibited superior mechanical properties in comparison to the pristine matrix, confirmed by both DMA and static stretching test. [ABSTRACT FROM AUTHOR]