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Metal organic frameworks (MOFs) are crystalline, three-dimensional structures with high surface areas and tunable porosities. Made from metal nodes connected by organic linkers, the exact properties of a given MOF are determined by node and linker choice. MOFs hold promise for numerous applications, including gas capture and storage. M2(4,4′-dioxidobiphenyl-3,3′-dicarboxylate)—henceforth simply M2(dobpdc), with M = Mg, Mn, Fe, Co, Ni, Cu, or Zn—is regarded as one of the most promising structures for CO2 capture applications. Further modification of the MOF with diamines or tetramines can significantly boost gas species selectivity, a necessity for the ultra-dilute CO2 concentrations in the direct-air capture of CO2. There are countless potential diamines and tetramines, paving the way for a vast number of potential sorbents to be probed for CO2 adsorption properties. The number of amines and their configuration in the MOF pore are key drivers of CO2 adsorption capacity and kinetics, and so a validation of computational prediction of these quantities is required to suitably use computational methods in the discovery and screening of amine-functionalized sorbents. In this work, we study the predictive accuracy of density functional theory and related calculations on amine loading and configuration for one diamine and two tetramines. In particular, we explore the Perdew–Burke–Ernzerhof (PBE) functional and its formulation for solids (PBEsol) with and without the Grimme-D2 and Grimme-D3 pairwise corrections (PBE+D2/3 and PBEsol+D2/3), two revised PBE functionals with the Grimme-D2 and Grimme-D3 pairwise corrections (RPBE+D2/3 and revPBE+D2/3), and the nonlocal van der Waals correlation (vdW-DF2) functional. We also investigate a universal graph deep learning interatomic potential's (M3GNet) predictive accuracy for loading and configuration. These results allow us to identify a useful screening procedure for configuration prediction that has a coarse component for quick evaluation and a higher accuracy component for detailed analysis. Our general observation is that the neural network-based potential can be used as a high-level and rapid screening tool, whereas PBEsol+D3 gives a completely qualitatively predictive picture across all systems studied, and can thus be used for high accuracy motif predictions. We close by briefly exploring the predictions of relative thermal stability for the different functionals and dispersion corrections. [ABSTRACT FROM AUTHOR]

We designed a trigonal symmetric imine-linked covalent organic framework (COF), TFPC-DAB, with control over the angularity of the building units, where a bent C2-symmetric diamine, such as 1,3-diaminobenzene (1,3-DAB or DAB), with an exo-angle of 120° was used instead of those with an exo-angle of 180°, in combination with a C3-symmetric trialdehyde, such as tri(4-formylphenoxy)cyanurate (TFPC). Its synthesis was accomplished by reacting the building units in a mixture of mesitylene/dioxane/6 M acetic acid under solvothermal conditions. The phase purity, thermal stability, and porosity of TFPC-DAB were established by various analytical techniques. Utilizing the Density Functional Tight Binding (DFTB+) simulation and Pawley refinement, the best fit of the small angle x-ray pattern was found to have an AA stacking of TFPC-DAB in the trigonal space group P3 with low refinement parameters. Such smart materials are in huge demand to detect hazardous corrosive chemicals, such as HCl and NH3. The dual features of electron deficient π-acidic triazine moiety and heteroatoms (N/O) from TFPC and electron rich phenyl units from DAB embodied in the framework enhance its luminescent property and thereby make it suitable for solvent-based HCl and NH3 sensing. The detection limits for HCl and NH3 in methanol were found to be 14 and 82 ppb, respectively. The effect of solvent polarity on the sensing studies was observed with much lower detection limits in dioxane: 2.5 and 11 ppb for HCl and NH3, respectively. A detailed theoretical calculation using density functional theory and configurational bias Monte Carlo modules was conducted for understanding interactions between the COF and HCl or NH3 analytes. [ABSTRACT FROM AUTHOR]

A gold surface is functionalized by chemisorption of the enantiopure N,N′-bis-[2,2′;5′,2″]tert-thiophene-5-yl methylcyclohexane-1,2-diamine (2T3N), a chiral oligothiophene derivative, via overnight incubation in a 2T3N ethanol solution. The Au|2T3N interface is characterized by x-ray photoelectron circular dichroism and comparing x-ray photoemission spectroscopy and electro-desorption results. Charge transmission at the Au|2T3N| solution interface is characterized by recording the cyclic voltammetry of the Fe(III)/Fe(II) reversible redox couple, finding a charge transfer rate constant, k°, variation from 1 × 10−1 to 3.3 × 10−2 cm s−1, when comparing the bare Au and the Au|2T3N interfaces, respectively. The "anomalous" high value of k° found for the chiral Au|2T3N interface can be rationalized on the basis of the chiral-induced spin selectivity effect, as further proved by magnetic–conductive atomic force microscopy measurements at room temperature. A spin polarization of about 30% is found. [ABSTRACT FROM AUTHOR]

We herein present a novel and an unexpected method for the synthesis of α-ketothioesters by the reaction of pyrrolidine with α-oxodithioesters followed by treatment with methyl iodide in methanol. One of the synthetic applications of α-ketothioesters for the synthesis of 2-acylbenzimidazoles by acid-catalyzed cyclocondensation with benzene-1,2-diamines is described. The probable mechanisms of formation of α-ketothioesters and 2-acylbenzimidazoles are proposed. [ABSTRACT FROM AUTHOR]

The recyclization of isocoumarins under the N‐nucleophile action is a well‐known route to different isoquinolones. But addition of functional groups in such substrates can provide more complicated nitrogen‐containing heterocycles. In this study, the easy formation of 3,4‐dihydro‐6H‐pyrazino[1,2‐b]isoquinolin‐6‐one system via the interaction of 3‐acylisocoumarins and ethane‐1,2‐diamines is demonstrated. As the acyl component of reaction, 3‐acetyl‐ and 3‐benzoylisocoumarins, 2,3‐dihydro‐1H‐benzo[c]chromene‐4,6‐dione, and heteroanalogs of 3‐acetylisocoumarin were successfully used; and the amino component was represented by ethane‐1,2‐diamine, some cyclic vicinal diamines, methyl 2,3‐diaminopropanoate, and N1‐methylethane‐1,2‐diamine. The variation of substrates gave different structures with 3,4‐dihydro‐6H‐pyrazino[1,2‐b]isoquinolin‐6‐one core; and the number of products can grow extremely because of this core's aptitude to reduction. Thus, 1,2,3,4‐tetrahydro‐6H‐pyrazino[1,2‐b]isoquinolin‐6‐ones, 1,2,3,4,11,11a‐hexahydro‐6H‐pyrazino[1,2‐b]isoquinolin‐6‐ones and 1,3,4,6,11,11a‐hexahydro‐2H‐pyrazino[1,2‐b]isoquinolines were synthetized by using various reduction methods for separate 3,4‐dihydro‐6H‐pyrazino[1,2‐b]isoquinolin‐6‐ones. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Chiral 1,3‐substituted fragments are ubiquitous in pharmaceutical molecules and natural products, prompting the development of numerous methods to access these structures. Nonetheless, devising synthetic routes for complex chiral architectures in practical applications typically demands years of expertise. Herein, we developed a nickel‐catalyzed enantioselective migratory arylboration reaction of allylboronic esters using a chiral 1,2‐diamine ligand, yielding a range of chiral 1,3‐bis(boronates) with high enantioselectivity. The protocol is characterized by its use of commercially available substrates, mild reaction conditions, user‐friendly procedures, and a broad substrate compatibility. Moreover, we demonstrate the practicality and application potential of this reaction by synthesizing several key drug intermediates. [ABSTRACT FROM AUTHOR]

An enantioselective arylation of isoxazoles with N‐Cbz‐protected azonaphthalenes is disclosed, affording a range of axially chiral arylisoxazoles in good yields and excellent enantiocontrol by utilizing chiral phosphoric acid. Cbz protecting group can be readily removed, resulting in five‐six membered axially chiral heterobiaryl amines bearing free amine maintaining enantiomeric purity. [ABSTRACT FROM AUTHOR]

This study describes the synthesis of N5‐(4‐(1H‐benzo[d]imidazol‐2‐yl)phenyl)‐N2‐phenylpyridine‐2,5‐diamine derivatives from Orthophenylenediamine (1) and 4‐aminobenzoic acid (2) and all the synthesized chemical moieties screened against a panel of cancer cell lines resulted in the identification compound 6 a with good anti‐cancer potential and a GI50 of 2.95 μM, 3.35 μM, 2.27 μM, 8.46 nM and 1.56 μM against MDAMB‐231, MCF‐7, A‐549, NCI‐H23 and A‐498 respectively. As the second greatest cause of death globally, cancer continues to pose a serious threat to public health. An essential enzyme called aromatase catalyses the last, rate‐limiting step in the production of oestrogens. As a well‐researched endocrine therapeutic strategy, aromatase inhibitors (AIs) efficiently block the production of oestrogen, which is necessary for aromatase activity. [ABSTRACT FROM AUTHOR]

In the present work, we reported the synthesis and characterization [single crystal X-ray diffraction technique, spectroscopic, etc.] of two new Ni(II) and Zn(II) coordination compounds, viz. [Ni(2,6-PDC)2]2[Ni(en)2(H2O)2]2[Ni(en)(H2O)4]·4H2O (1) and [Zn(2,6-PDC)(Hdmpz)2] (2) (where 2,6-PDC = 2,6-pyridinedicarboxylate, en = ethylene-1,2-diamine, and Hdmpz = 3,5-dimethyl pyrazole). Compound 1 is found to crystallize as a multicomponent Ni(II) compound with five discrete complex moieties, whereas compound 2 is isolated as a mononuclear Zn(II) compound. A deep analysis of the crystal structure of 1 unfolds unusual dual enclathration of guest complex cationic moieties within the supramolecular host cavity stabilized by anion–π, π-stacking, N–H⋯O, C–H⋯O, and O–H⋯O hydrogen bonding interactions. Again, the crystal structure of compound 2 is stabilized by the presence of unconventional C–H⋯π(chelate ring) interactions along with C–H⋯O, C–H⋯N hydrogen bonding, π-stacking, and C–H⋯π(pyridyl) interactions. These non-covalent interactions were further studied theoretically using density functional theory (DFT) calculations, molecular electrostatic potential (MEP) surfaces, non-covalent interaction (NCI) plot index, and quantum theory of atoms in molecules (QTAIM) computational tools. The computational study displays that π-stacking or H bonds greatly tune the directionality of compound 1, although non-directional electrostatic forces dominate energetically. For compound 2, a combined QTAIM/NCI plot analysis confirms the presence of unconventional C–H⋯π(chelate ring) interactions along with other weak interactions obtained from the crystal structure analysis. Further, the individual energy contributions of these weak yet significant non-covalent interactions have also been determined computationally. [ABSTRACT FROM AUTHOR]

Ring size-dependent diastereoselective coordination of unsymmetrical diamines containing one azacyclic nitrogen and one exocyclic nitrogen to [(η5-C5Me5)MCl]+ cores where M = Rh, Ir and [Ru(η6-cymene)Cl]+ is reported herein. Total stereoselectivity was observed with the six- and seven-membered azacycles, whereas the five-derivative proved poorly selective. All complexes were active for transfer hydrogenation but showed no enantioselectivity with prochiral ketones. [ABSTRACT FROM AUTHOR]

Our team created and produced an innovative range of bioactive disperse dyes, depending on the functionalizing neocryptolepines connected to an azo-benzene sulfonyl moiety using various diaminoalkyl linker chains. These types of dyes are successfully applied to the creation of pastes for silkscreen printing of polyester fabric. To ascertain the dye strength, polyester printed samples underwent testing for washing, rubbing, perspiration, sublimation, and light fastness. In addition, L*, a*, and b* were used to evaluate the hue of the color dyes. Using the colony forming unit (CFU) method, the antibacterial activity of the printed polyester fabrics was assessed. The anti-gram positive actions of fabric samples treated with 6c and 6f against S. aureus were encouraging. In contrast, fabrics treated with 6b, 6d, and 6e showed only mild anti-gram negative activity against the test bacterium L. monocytogenes. [ABSTRACT FROM AUTHOR]

To improve the thermodynamic and mechanical properties of asymmetric polyimide (PI), a method to enhance the linearity of PI by using a structural reorganization approach was designed. First, two novel diamines containing benzimidazole and benzoxazole groups, namely PADBZ and PDBOA, were constructed and synthesized. Thereafter, two new kinds of PI films (PADBZ‐PMDA and PDBOA‐PMDA) were prepared and polymerized with 1,2,4,5‐benzenetetracarboxylic anhydride (PMDA). Based on structural reorganization, PADBZ‐PMDA and PDBOA‐PMDA had repeating units of the same chemical composition and different linearity with PABZ‐BPDA and BOA‐BPDA, respectively. Comparing PADBZ‐PMDA and PABZ‐BPDA, due to the transfer in the position of benzene, PADBZ‐PMDA with high linearity showed the improved heat resistance (Tg up to 448°C), dimensional stability (CTE down to 2.3 ppm/K) and mechanical properties. PDBOA‐PMDA and BOA‐BPDA had the same situation. This study provided a unique solution to enhance the performances of PI by increasing the linearity using a structural reorganization approach. [ABSTRACT FROM AUTHOR]

Synthesis and structural characterization of a family of germanium‐dioxolene complexes with ditopic N‐donor ligands (L1‐L5) (L1=1,2‐bis(pyridin‐2‐ylmethylene)hydrazine L2=1,6‐bis‐(pyridin‐2‐yl)‐2,5‐diaza‐1,5‐hexadiene, L3=N,N‐bis(pyridin‐2‐ylmethylene)‐1,4‐benzenediamine, L4=N,N‐bis(pyridin‐2‐ylmethylene)‐(biphenyl)‐4,4‐diamine, L5=2,2’‐azopyridine) is reported. The reaction of germanium bis‐catecholate with bridging ligands L1 – L4, differing by the nature of the linker between pyridine sites gives rise to dinuclear digermanium complexes (36Cat2Ge)2L1−4 (36Cat=dianion of 3,6‐di‐tert‐butylcatechol) 1–4 of DMAMD type (donor‐metal‐acceptor‐metal‐donor) with a charge transfer in the UV‐Vis region. In opposite, the interaction of the 36Cat2Ge with 2,2’‐azopyridine (L5) results in the two‐electron transfer from the donor 36Cat2− ligands to the azopyridine bridge forming stable open‐shell complex 5 [(36SQ)(36CatGe)]2(L5)2− (36SQ=radical‐anionic semiquinonate ligand). Molecular structures of compounds 3 and 5 were determined by single crystal X‐ray diffraction analysis. Electronic structures of complexes 1–5 were studied by means of DFT calculations. [ABSTRACT FROM AUTHOR]

Visible light‐induced polymerization, as a promising and green strategy, is showing great potential in preparing value‐added polymers. Herein, a visible light photoredox catalysis method is reported to afford a library of polyamide with high yields (up to 99%) and high molecular weights (Mws) (up to 71 000 g mol−1). Dithioacids and diamines as the monomers, and 9‐mesityl‐10‐methylacridinium tetrafluoroborate (Mes‐Acr‐MeBF4) as the organic photoredox catalyst give the polyamides with structural diversity in air under mild conditions without extra metal, base, or additives. [ABSTRACT FROM AUTHOR]

The reductive amination of 1,6‐hexanediol with ammonia is one of the most promising green routes for synthesis of 1,6‐hexanediamine. Herein, we developed a phosphorous modified Ni catalyst of Ni−P/Al2O3. It presented satisfactory improved selectivity to 1,6‐hexanediamine in the reductive amination of 1,6‐hexanediol compared to the Ni/Al2O3 catalyst. The phosphorous tended to interact with Al2O3 to form AlPOx species, induced Ni nanoparticle to be flatter, and the decrease of strong acid sites, the new‐formed Ni−AlPOx−Al2O3 interface and the flatter Ni nanoparticle were the key to switch the dominating product from hexamethyleneimine to 1,6‐hexanediamine. This work develops an efficient catalyst for production of 1,6‐hexanediamine from the reductive amination of 1,6‐hexanediol, and provides a point of view about designing selective non‐noble metal catalysts for producing primary diamines via reductive amination of diols. [ABSTRACT FROM AUTHOR]

Isohexide‐derived diamines are considered preferred precursors for the production of biobased polyurethanes and polyamides. However, current synthesis methods from isohexides suffer from serious issues concerning selectivity and the recyclability of the process auxiliaries (e. g. homogeneous catalysts), which renders a translation to the industry highly unlikely. Here, we report on the production of such diamine building blocks, via a tandem electrooxidation – reductive amination process in which the process auxiliaries can be easily recycled. The application of (immobilized) TEMPO in combination with simple halides (e. g. NaBr) in the electrochemical step even enables the oxidation of the sterically hindered exo‐OHs of the isohexides to the corresponding diketones (yield up to 99 %). In the subsequent reductive amination, the produced ketones are atom‐efficiently converted to isohexide diamines utilizing NH3, H2, and Ru/C and an acid resin cocatalyst. [ABSTRACT FROM AUTHOR]

Diglycidyl ether of bisphenol A (DGEBA), a key intermediate for epoxy resins, provides strong adhesion, processability and the resulting thermoset boasts high cross linking density. However, the inherent brittleness and susceptibility to cracking restrict its advanced applications. To overcome these drawbacks, CO2 fixed cyclic carbonate from castor oil (CCO) was synthesized from epoxidised castor oil (ECO) and used in varying quantities as a toughening agent for amine cured DGEBA. Different amines have been utilized to cure the epoxy and to study the structure–property relationship by fixing the amount of CCO. The inclusion of 10% CCO resulted in improvement in the tensile strength, storage modulus, flexural modulus, and impact strength of the epoxy‐urethane hybrid. Moreover, the epoxy‐urethane networks had reduced cross linking density imparted by the fatty acid units of CCO and the presence of unreacted carbonate groups facilitated molecular movement, thereby contributing to energy dissipation during the deformation process. Further incorporation of the CCO lowers the mechanical properties of the hybrids due to a reduction in cross linking density. Trimethylolpropane tris[poly(propyleneglycol)amine terminated] ether cured system exhibited the highest thermal stability compared to hexamethylene diamine, isophorone diamine, and 4,7,10‐trioxa‐1,13 tridecanediamine. The Tg decreased as the CCO content increased, while the water contact angle increased. [ABSTRACT FROM AUTHOR]

The article discusses the polymerization scheme of benzoxazine monomer based on 4,4′‐diaminodiphenylmethane (P‐ddm) and the chemical structure of polybenzoxazine based on it poly(P‐ddm). The polymerization behavior of benzoxazine P‐ddm is studied using differential scanning calorimetry (DSC). Solid‐state 13C MAS NMR is used to determine the chemical structure of poly(P‐ddm). It is revealed that the сhemical structure of poly(P‐ddm) predominantly consists not of phenolic Mannich bridges, as expected, but of methylene bridges, which indicates the process of deamination of phenolic Mannich bridges. However, no weight loss associated with the expected release of free amine during this process is detected. This may indicate the incorporation of a diamine moiety into the polymer chain through the formation of imine bonds, the signal of which is detected in the 13C MAS NMR and FTIR spectra of the poly(P‐ddm), and on the 1H and 13C NMR spectra of model polybenzoxazine based on p‐cresol and 4,4′‐diaminodiphenylmethane poly(pC‐ddm). Based on the data obtained, a hypothesis is put forward about the formation of a network polymer, the structure of which consists mainly of methylene and imine units. [ABSTRACT FROM AUTHOR]

This article presents a new method for synthesizing quinoxalines, a versatile class of compounds with applications in medicine, agriculture, and materials science. The authors demonstrate that their method, which uses meglumine sulfate as a catalyst, is simple, efficient, and produces high-quality products. The article includes experimental details and characterization data for the synthesized compounds, which include various quinoxaline derivatives. The document also includes acknowledgments and a disclosure statement. [Extracted from the article]

[Display omitted] Polyimide (PI) aerogels possess significant potential for various applications due to their outstanding mechanics and thermal insulation. However, a major drawback of these aerogels is their susceptibility to moisture, which not only compromises their insulative performance but also leads to an increase in weight. To address this issue, we have developed a moisture-resistance technique by incorporating a long-chain hydrophobic barrier at the ortho position relative to the imide groups to enhance the moisture-resistance of the PI aerogels. This approach involved using a series of diamines with hydroxyl groups strategically located at the ortho position of imide groups as reactants. The resulting PI aerogels demonstrated a significant improvement in water resistance, reducing water-uptake to merely one-tenth of that recorded in unmodified samples. Furthermore, the effectiveness of this hydrophobic modification was validated through molecular dynamics simulations, which indicated a diffusion coefficient of 4.41 × 10−11 m2/s after modification. These findings represent a considerable advancement in developing effective methods for hydrophobic modification of PI aerogels, with potential applications in aerospace, electronic communications, and environmental protection. [ABSTRACT FROM AUTHOR]

Encapsulation of metal particles into zeolites is an attractive strategy for stabilizing metal species. Nevertheless, most metal cations tend to precipitate under basic and hydrothermal conditions without the use of effective anchoring agents. Herein, low‐cost diamines of ethylenediamine and propanediamine were selected as effective chelators, which stabilized the Cu species under basic conditions and then anchored them into the framework of MFI (silicate‐1) during the hydrothermal process. The obtained Cu@MFI−R catalyst showed >96 % ethanol conversion and 98 % acetaldehyde selectivity in the 300 h time on stream, demonstrating superior advantages over the impregnation method prepared Cu/MFI catalysts. Characterization of Cu@MFI−R catalysts revealed that Cu nanoparticles were fixed in the framework of MFI, producing abundant Cu+ species for ethanol conversion. Additionally, the spatial confinement effects inhibited Cu+ reduction and aggregations, affording a high catalyst stability. Differently, over Cu/MFI catalysts, the unconfined Cu+ species were prone to be reduced into Cu0 during the reaction, resulting in the Cu particles aggregation and activity depression. [ABSTRACT FROM AUTHOR]

The asymmetric catalytic synthesis of 1,2-diamines has received considerable interest, especially in the last ten years, due to their presence in biologically active compounds and their applications for the development of synthetic building blocks, chiral ligands and organocatalysts. Synthetic strategies based on C–N bond-forming reactions involve mainly (a) ring opening of aziridines and azabenzonorbornadienes, (b) hydroamination of allylic amines, (c) hydroamination of enamines and (d) diamination of olefins. In the case of C–C bond-forming reactions are included (a) the aza-Mannich reaction of imino esters, imino nitriles, azlactones, isocyano acetates, and isothiocyanates with imines, (b) the aza-Henry reaction of nitroalkanes with imines, (c) imine–imine coupling reactions, and (d) reductive coupling of enamines with imines, and (e) [3+2] cycloaddition with imines. C–H bond forming reactions include hydrogenation of C＝N bonds and C–H amination reactions. Other catalytic methods include desymmetrization reactions of meso-diamines. [ABSTRACT FROM AUTHOR]

A photoinduced EnT-mediated generation of sulfonamidyl radicals has been accomplished using rationally designed iminophenylacetic acid oxime ester reagents under metal-free conditions. This approach offers a mild, regio- and diastereoselective synthesis of N-sulfonyl diamines via diamination of alkenes and (hetero)arenes. [ABSTRACT FROM AUTHOR]

Chiral imidazolidin-2-ones are a kind of important N-heterocycles in bioactive molecules and can be converted to valuable chiral vicinal diamines. It is of great significance to develop catalytic asymmetric transformations for the synthesis of chiral N -heterocycles which play a significant role in drug development. Herein, an asymmetric intramolecular C(sp³)--H amination of N-benzoyloxyurea via 1,5-hydrogen atom transfer (HAT) is developed by using earth-abundant iron as the catalyst and chiral amino-acid derived phenanthroline as ligand, affording a series of chiral imidazolidinones in moderate-to-good yields (up to 68%) and enantiomeric ratios (up to 81:19). It is worth noting that this is one of the very few examples of iron-catalyzed enantioselective intramolecular C(sp³)--H aminations realized with a nonenzymatic catalyst. [ABSTRACT FROM AUTHOR]

Controlling hybrid material properties by simple monomer design offers an elegant pathway to prepare thermoset adhesives with tunable properties. Herein, biobased hybrid polyhydroxyurethane/polyepoxy is prepared starting from partially carbonated cashew nut shell epoxy derivatives (NC514) and m‐xylene diamine (MXDA). The curing reactions, that is, epoxy‐amine and cyclic carbonate aminolysis, monitored by ATR‐IR spectroscopy at 50 °C are found to be concomitant yielding highly homogeneous materials. Hybrid networks are extensively characterized by swelling tests, TGA, DMA, DSC, tensile tests, rheology, and lap‐shear‐test on aluminum substrates. The introduction of hydroxyurethane moieties within the epoxy‐amine networks enhanced the adhesion properties (up to 20% compare to neat epoxy resins) by combining hydrogen bonding capability and vitrimeric properties (thermoset able to flow). Rheological characterizations and reprocessing tests demonstrated that hybrid adhesives with up to 47 mol% of cyclic carbonate groups are capable of covalent exchange (internally catalyzed by tertiary amine) while keeping similar thermomechanical properties and enhanced adhesion strength compare to the permanent epoxy network. [ABSTRACT FROM AUTHOR]

The nanocomposites of polythiourethane (PTU) with Fe3O4 were fabricated via an isocyanate-free approach. The nanocomposites simultaneously had the reprocessing, shape memory and photothermal properties. First, a linear PTU carrying a plethora of thiol groups was synthesized via the ring opening polyaddition between a bicyclic trithiocarbonate and a poly (propylene oxide) diamine. In the meantime, the surfaces of Fe3O4 nanoparticles were functionalized with thiol groups. Second, the co-crosslinking between the linear PTU and the thiol-functionalized Fe3O4 was performed via the coupling of thiol radicals with a radical initiator. Notably, the nanocomposites of PTU with Fe3O4 were successfully obtained with the fine dispersion of Fe3O4 nanoparticle in PTU matrix. Compared to control PTU, the nanocomposites displayed the improved thermomechanical properties. More importantly, the nanocomposites had reprocessing properties. The dynamic exchange of disulfide bonds is responsible for the reprocessing behavior. Owing to the crosslinking with disulfide bonds, PTU had shape memory properties. Notably, the incorporation of Fe3O4 nanoparticles was capable of improving the shape memory properties. In addition, the nanocomposites displayed the photothermal properties with the incorporation of Fe3O4 nanoparticles. The photothermal conversion behavior can be utilized to trigger the shape recovery of the nanocomposites under near-infrared light irradiation and in a non-contact fashion. [ABSTRACT FROM AUTHOR]

A series of nine new soft salts based on two platinum(II) complexes, namely ([Pt(C^N)(CN)2]−[Pt(C^N)(en)]+) (en = ethane-1,2-diamine), has been developed and synthesized. Their photophysical properties in both solution and the solid state were described. All soft salt complexes exhibit phosphorescence emission with PLQY in the solid state up to 0.36. Most of these materials displayed aggregation-induced emission (AIE) or aggregation-induced emission enhancement (AIEE) in water/DMSO solutions as the water ratio increased. Structure–property relationships were analyzed in relation to emission properties. The presence of the free nitrogen atoms in soft salt complexes with a C^N pyrimidine-based ligand allowed for reversible sensitivity to acidic vapors, resulting in the quenching of phosphorescence emission. Additionally, for selected soft salts, we described reversible vapochromism behaviour, making these new materials interesting for multi-detection purposes in anti-counterfeiting applications. [ABSTRACT FROM AUTHOR]

A bipolar polymer cathode material, containing redox-active azo benzene and diamine moieties, was synthesized for sodium-ion batteries. The n-type azo group and p-type amine group enable a wide cutoff window with an initial capacity of 93 mA h g−1 at 50 mA g−1 and a high voltage plateau at ∼3.3 V. [ABSTRACT FROM AUTHOR]

The preparation of Fe(II) complexes combining monodentate NCX− (X = S or Se) and the tetradentate Schiff base chiral ligands RR-L1 and SS-L1 = (RR- or SS-L1 = 1R,2R or 1S,2S)-N1,N2-bis(pyridin-2-ylmethylen)cyclohexane-1,2-diamine in acetone results in an unexpected reaction. Thus, four enantiomerically pure compounds of formulas [Fe(RR-S-L2)(NCX)2] and [Fe(SS-R-L2)(NCX)2] (X = S or Se) are formed by the new asymmetrical ligand L2. In L2, one acetone solvent molecule is incorporated into the ligand forming a bond with the C atom of one of the two CN imine groups of L1, which is transformed into an amine (Mannich reaction). This reaction is diastereoselective as the incorporation of acetone leads to an asymmetric C adjacent to the NH group with opposite chirality S- or R- to that of the cyclohexane carbons (RR- or SS-, respectively). Therefore, L2 contains three C chiral centers. Structural and magnetic characterization of these compounds demonstrates that they show in the bulk a gradual spin-crossover behavior and LIESST effect. Interestingly, the presence of an intramolecular hydrogen bond between the integrated acetone molecule and the NH group can trigger a secondary stimuli-responsive behavior in the system. Therefore, by changing the solvent polarity, the color of the complex in solution can be easily tuned. [ABSTRACT FROM AUTHOR]

Since the seminal work presented by Olah in 1966 on fluorinated carbocations, several strategies have been presented to introduce fluorinated moieties in polymer backbones via carbocation chemistry. The hexafluoroisopropylidene (6F) group is well known for its ability to enhance thermal properties and processability of polymers. However, its direct electrophilic incorporation into polymers has been largely ignored due to the challenges posed by activating hexafluoroacetone monomer for electrophilic aromatic substitution (EAS). In this article, we review the role of fluorinated carbocations from 1966 up to our recent versatile fluoroalkylation strategy to directly enchain the 6F group in polymers. Via EAS interfacial polymerization we reacted hexafluoroacetone trihydrate (HFAH) with aromatic monomers in triflic anhydride (Tf2O) and 1,2-dichloroethane (DCE) with Aliquat® 336. In addition, the polymerization of dibenzo-1,4-dioxin with HFAH is presented. A semi-fluorinated diol, 4,4′-bis(2-hydroxyhexafluoroisopropyl)diphenyl ether, was synthesized by this method and used to prepare the first reported polycarbonate with hexafluoroisopropoxy groups –C(CF3)2O– incorporated in the main chain via polycondensation. Polysilyl ethers were also prepared from this diol. Additionally, we briefly mention Carraher's legacy in the synthesis of metal-containing polymers via reactions of group IVB metallocene dichloride with dinucleophiles (diamines, diol, dicarboxylic acids, and dithiols) in solution and interfacial conditions in terms of electrophilic vs nucleophilic polycondensation. The new acidic, sterically hindered semi-fluorinated diol and bisphenol AF were reacted with group IVB metallocene dichloride in attempts to form metallocene condensation polymers with improved solubility. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion hybrid supercapacitors (Zn‐HSCs) are promising devices for sustainable and efficient energy storage. However, they suffer from a limited energy density compared to lithium‐ion batteries. This limitation can be overcome by developing novel electrode materials, with covalent organic frameworks (COFs) standing out as a particularly intriguing option. Herein, peri‐xanthenoxanthene (PXX) has been integrated for the first time into a COF scaffold to take advantage of its straightforward synthesis, chemical stability, π‐conjugated backbone, and heteroatom content endowing reversible redox reactions at low potentials. Two novel hexagonal COFs have been designed and synthesized by tethering of a PXX‐diamine unit having a C2 symmetry with two distinct tris‐aldehydes acting as C3‐symmetric cornerstones, i.e., triformyl benzene (TFB) and triformylphloroglucinol (Tp), ultimately yielding COF PXX(PhNH2)2‐TFB and COF PXX(PhNH2)2‐Tp, respectively. As cathodes in Zn‐HSCs, COF PXX(PhNH2)2‐Tp exhibits a remarkable specific capacitance, energy, and power densities (237 F g−1, 106.6 Wh kg−1, and 3.0 kW kg−1, respectively), surpassing those of COF PXX(PhNH2)2‐TFB (109 F g−1, 49.1 Wh kg−1, and 0.67 kW kg−1). Importantly, both COFs display outstanding long‐term stability, over 5000 charge/discharge cycles, with capacitance retention >92%. These findings underscore the potential of PXX‐based COFs as high‐performance cathode materials for HSCs, thereby offering a promising new avenue for energy storage technologies. [ABSTRACT FROM AUTHOR]

It is generally accepted that adjacent guanine residues in DNA are the primary target for platinum antitumor drugs and that differences in the conformations of the Pt-DNA adducts can play a role in their antitumor activity. In this study, we investigated the effect of the carrier ligand cis-1,3-diaminocyclohexane (cis-1,3-DACH) upon formation, stability, and stereochemistry of the (cis-1,3-DACH)PtG2 and (cis-1,3-DACH)Pt(d(GpG)) adducts (G = 9-EthlyGuanine, guanosine, 5′- and 3′-guanosine monophosphate; d(GpG) = deoxyguanosil(3′-5′)deoxyguanosine). A peculiar feature of the cis-1,3-DACH carrier ligand is the steric bulk of the diamine, which is asymmetric with respect to the Pt-coordination plane. The (cis-1,3-DACH)Pt(5′GMP)2 and (cis-1,3-DACH)Pt(3′GMP)2 adducts show preference for the ΛHT and ∆HT conformations, respectively (HT stands for Head-to-Tail). Moreover, the increased intensity of the circular dichroism signals in the cis-1,3-DACH derivatives with respect to the analogous cis-(NH3)2 species could be a consequence of the greater bite angle of the cis-1,3-DACH carrier ligand with respect to cis-(NH3)2. Finally, the (cis-1,3-DACH)Pt(d(GpG)) adduct is present in two isomeric forms, each one giving a pair of H8 resonances linked by a NOE cross peak. The two isomers were formed in comparable amounts and had a dominance of the HH conformer but with some contribution of the ΔHT conformer which is related to the HH conformer by having the 3′-G base flipped with respect to the 5′-G residue. [ABSTRACT FROM AUTHOR]

This study presents the development of a series of biobased polyesteramides, labeled as PEAF1–3, via a greener approach, from bisfuranic diamine and commercially available aliphatic diesters of varied chain lengths. The resulting polymers showed reasonable molar masses, in accordance with inherent viscosities ranging between 0.19 and 0.35 dL/g. Evaluation of their thermal properties by thermogravimetric analysis and differential scanning calorimetry showcased excellent thermal stability (Td,max ≥ 335 °C), amorphous character and low glass transition temperature (Tg) decreased with the increasing chain length. Moreover, notable finding was the exceptional stability of these polyesteramides against both hydrolytic and oxidative degradation processes. This resistance underscores their potential as highly stable materials, making them promising for various applications where durability and resistance to degradation are crucial. [ABSTRACT FROM AUTHOR]

A simple, convenient, efficient and environmentally benign method has been developed for the synthesis of benzo[3,4-a]phenazin-5-ol as well as benzo[f]pyrido[2,3-b]quinoxalin-5-ol derivatives via the condensation of lawsoneand o-phenylenediamines or pyridine-2,3-diamines respectively by using a catalytic amount of trisodium citrate as an efficient, commercially available and low cost organo-catalyst in aqueous ethanol at room temperature. Mild reaction conditions, use of metal-free organocatalyst, nontoxic solvent, energy efficiency, no column chromatographic separation, gram scale production and reusability of the catalyst containing solvent media are some of the notable advantages of our developed protocol. [ABSTRACT FROM AUTHOR]

It was shown that copolyimides based on adamantane-containing diamine and dianhydrides of 2,3,3′,4′-biphenyltetracarboxylic acid (a-BPDA) and 5,5′-(1,1,1,3,3,3-hexafluoropropane-2,2-diyl)bis(2-benzofuran-1,3-dione) (6FDA) are characterized by good thermal-oxidative properties (T5% = 465–485 °C) and a high optical transparency (T400 = 60–80%) in comparison with copolyimides based on the same dianhydrides and 2,2′-bis(trifluoromethyl)biphenyl-4,4′-diamine (TFBA), containing bulky trifluoromethyl fragments (T400 = 38–67%). [ABSTRACT FROM AUTHOR]

New oligoether diamines were synthesized via the step of obtaining oligoether diacrylates, followed by their subsequent reaction with 3-aminomethyl-3,5,5-trimethylcyclohexylamine. A series of urethane-containing elastomers based on them was obtained. The polymers were evaluated by differential scanning calorimetry, and their deformation and strength characteristics were also estimated. It was demonstrated that a low glass transition temperature is characteristic of all the polymers. [ABSTRACT FROM AUTHOR]

The homoleptic trifluoromethyl‐palladium(II) complex [Pd(CF3)4]2− (1) is shown to be highly active towards amines. Thus, when treated with primary amines RNH2, it readily undergoes aminolysis of one of the CF3 ligands affording the isocyanide complexes [(CF3)3Pd(CNR)]− (R=aryl). In this process the original CF3 group undergoes total defluorination. Interestingly, the reaction of 1 with secondary amines R2NH proceeds with loss of just two F‐substituents, whereby the Fischer‐type fluoroaminocarbene complexes [(CF3)3Pd(CFNR2)]− are formed (R=Et, Ph). The reaction of 1 with diamines affords different [(CF3)3Pd(NHC)]− complexes containing sterically non‐demanding NHC ligands. Representative examples of various topologies are reported based on the common imidazolidin‐2‐ylidene or benzimidazolin‐2‐ylidene rings as well as the expanded‐ring perimidin‐2‐ylidene. This metal‐tailored synthetic route, where a CF3 group acts as a pre‐carbenic unit, is unprecedented in the vast NHC‐chemistry. It takes place under very mild conditions and is envisaged to be extensible to other non‐isolable NHC ligands. The key difluorocarbene intermediate [(CF3)3Pd(CF2)]− is experimentally detected. [ABSTRACT FROM AUTHOR]

To make the colorless polyimides (CPIs) suitable for the application of flexible display technology, the polyimide (PI) films need to have both good optical properties and thermal properties. To get the wanted properties, 2‐(2‐methyl‐4‐(2‐methyl‐4‐aminobenzamido)phenyl)‐5‐(2‐methyl‐4‐aminobenzamido)‐N‐phenylbenzimidazol (5a) and 2‐(2‐methyl‐4‐(2‐trifluoromethyl‐4‐aminobenzamido)phenyl)‐5‐(2‐trifluoromethyl‐4‐aminobenzamido)‐N‐phenylbenzimidazol (5b) were synthesized, which both contained benzimidazole and bis‐amide structures. Two kinds of PI films were polymerized with cyclobutane‐1,2,3,4‐tetracarboxylic dianhydride (CBDA). With the contribution of side groups (CH3 or CF3), the resulting PI films presented relatively superior optical properties (transmittance at 400 nm was 59% and 68% respectively) and low coefficient of thermal expansion (CTE = 22 and 25 ppm K−1). These good properties suggest that these PI films have the potential for flexible display usage. [ABSTRACT FROM AUTHOR]

The chemoselective N-H insertion of unsymmetrical diamines into carbene is a longstanding challenge. A simple copper-catalyzed strategy for synthesizing C-substituted piperazinones is described, employing easily accessible diazo compounds and 1,2-diamines. The reaction proceeded via chemo-selective carbene insertion at the comparatively less nucleophilic amine, followed by instantaneous cyclization. The protocol was further extended to access NH-free piperazinone, and the synthesis of a Mianserin derivative. [ABSTRACT FROM AUTHOR]

Tetrakis-benzimidazoles draw attention with their structural similarities to ethylenediaminetetraacetic acid (EDTA) which is a medication used in the management and treatment of heavy metal toxicity, as well as having many different derivatives. In addition to the tetradentate feature due to the donor characteristic of the C=N nitrogen atom in each benzimidazole unit, there are also tetrakis-benzimidazole derivatives that show ligand properties up to octadentate through donor atoms such as N and O in the bridge units. The applications of tetrakis-benzimidazole derivatives and various metal complexes in many fields such as corrosion inhibitor, catalyst, enzyme inhibitor, superoxide dismutase, catalase activity, superoxide oxidase, DNA affinity, determination of H2O2, were investigated. In this study, a comprehensive review was conducted on N,N,N',N'-tetrakis(1H-benzimidazol-2-ylmethyl)ethane-1,2-diamine (EDTB), a hexadentate tetrakis-benzimidazole derivative. Synthesis routes, properties, various complexes of EDTB and its derivatives, their structural features and application areas have been reviewed and compiled in order to be useful for researchers who will work in this field. [ABSTRACT FROM AUTHOR]

This study aims to advance the field of green chemistry and catalysis by exploring alternatives to conventional non-renewable energy sources. Emphasis is placed on hydrogen as a potential fuel, with a focus on the catalytic properties of Ni(II) complexes when coordinated with o-phenylenediamine and diimine ligands. We report the synthesis and comprehensive characterization, with various physical and spectroscopic techniques, of three heteroleptic Ni(II) complexes: [Ni(1,10-phenanthroline)(o-phenylene diamine)] (1), [Ni(2,2-dimethyl-2,2-bipyridine)(o-phenylene diamine)] (2), and [Ni(5,5-dimethyl-2,2-bipyridine)(o-phenylene diamine)] (3). The catalytic activity of these complexes for hydrogen evolution was assessed through photochemical studies utilizing visible light irradiation. Two distinct photosensitizers, fluorescein and quantum dots, were examined under diverse conditions. Additionally, their electrocatalytic behavior was investigated to elucidate the hydrogen evolution reaction (HER) mechanism, revealing a combined proton-coupled electron transfer (PCET)/electron-coupled proton transfer (ECPT) mechanism attributed to the chemical nature of the diamine ligand. The influence of ligand substituent position, ligand chemical nature, and photosensitizer type on catalytic performance was systematically studied. Among the complexes investigated, complex 2 demonstrated superior catalytic performance, achieving a turnover number (TON) of 3357 in photochemical experiments using fluorescein as a photosensitizer. Conversely, complex 1 exhibited the highest TON of 30,066 for HER when quantum dots were employed as the photosensitizer. [ABSTRACT FROM AUTHOR]

Viscoelastic surfactants (VES) are often used as viscous diverters in acidizing stimulation to prolong the acid consumption time and maximize zonal coverage of the acid for improving well productivity. However, the ceiling temperature of commercial VES cannot exceed 120 °C in practical use because of the poor thermal stability and fragile molecular structure, hindering their implementation in hightemperature oil reservoirs, i.e., ≥150 °C. Here we synthesized a novel C22-tailed diamine, N-erucaminopropyl-N,N-dimethylamine (EDPA), and examined comparatively its rheological behavior, assemblies morphology and molecular stability in 20 wt% HCl with a commercial VES, erucyl dimethyl amidopropyl betaine (EDAB). The feasibility of EDPA for acidizing stimulation was assessed by acid etching of carbonate rock with its HCl solution at 150 °C. Rheological results showed that the 2.5 wt% EDPAe20 wt% HCl solution maintains stable viscosity of 90 mPa s at 150 °C for 60 min, while that of 2.0 wt% EDAB HCl solution is just 1 mPa s under identical conditions. 1H NMR spectra and cryo-TEM observations revealed that the chemical structure and self-assembled architectures of EDPA remained intact in such context, but the EDAB suffered from degradation due to the hydrolysis of the amide group, accounting for the poor heat-resistance and acid-tolerance. The reaction rate of 2.5 wt% EDPA HCl solution with carbonate rock was one order of magnitude lower than that of 20 wt% HCl solution at 150 °C, underpinning the potential of EDPA to be used in the high-temperature reservoirs acidizing. This work improved the thermal tolerance of VES in highly concentrated HCl solution, paving a feasible way for the acidization of high-temperature reservoir environments (~150°C). [ABSTRACT FROM AUTHOR]

1,3-bis((1H-1,2,4-triazol-1-yl)methyl)hexahydropyrimidine was readily prepared by cyclocondensation of propane-1,3-diamine with a mixture of (1H-1,2,4-triazol-1-yl)methanol and formaldehyde. The 1H- and 13C-NMR spectroscopic data of this ligand have been fully assigned and are consistent with the molecular structure. The crystalline structure of the compound was fully determined by single crystal X-ray diffraction at 150 K and at room temperature, together with the isobaric thermal expansion. Finally, during the first heating, DSC measurements showed no phase transition up to the melting temperature at 385.1 K (111.9 °C). [ABSTRACT FROM AUTHOR]

We herein report a solvent‐free, oxidative coupling reaction of alcohols with aromatic diamines in air. 9‐Azabicyclo[3.3.1]nonan‐N‐oxyl (ABNO) in combination with a manganese(II) catalyst, serves to effectively promote the reaction, leading to the selective synthesis of 2‐substituted benzimidazoles and 1,2‐disubstituted benzimidazoles. [ABSTRACT FROM AUTHOR]

Smart solvatochromic isocyano-aminoarenes (ICAArs) have been gaining attention owing to their unique photophysical, antifungal and anticancer properties. Using a simple dehydration reaction with in situ-generated dichlorocarbene, we prepared 2-amino-7-isocyanofluorene (2,7-ICAF). We studied the effect of the longer polarization axis provided by the fluorene core on the spectral properties and we also compared it to those of the starting diamine. 2,7-ICAF shows a clear solvatochromic behavior close to the blue part (370–420 nm) of the visible spectrum. Quantum chemical calculations show internal charge transfer (ICT) between the donor amino and the electron-withdrawing isocyano groups. 2,7-ICAF has high molar absorptivity (ε = 15–18·103 M−1cm−1) and excellent quantum yield (Φf = 70–95%) in most solvents; however, its fluorescence is completely quenched in water. The high brightness (ε·Φf) and close to zero quantum yield in water may be favorable in biolabeling applications, where background fluorescence should be kept minimal. Overall, 2,7-ICAF shows enhanced photophysical properties compared to its previously investigated relative 4-amino-4′-isocyano-1,1′-biphenyl (4,4′-ICAB). [ABSTRACT FROM AUTHOR]

The current landscape of chiral covalent organic frameworks (COFs) predominantly centered on constructing asymmetric molecular-scale chirality, often introducing an inherent contradiction to the COF symmetry and limiting diversity. Herein, we overcome these challenges by achieving chiral transfer between one-dimensional (1D) imine linear polymers (LPs) and two-dimensional (2D) network β-ketoenamine COFs composed of achiral monomers. We successfully synthesize several 1D imine LPs with mesoscopic helical chirality, comprising achiral C2-symmetric terephthalaldehyde and diamine linkers in a chiral supramolecular transcription system. Leveraging the irreversible tautomerism mechanism within the linker replacement approach, terephthalaldehyde (TPA) units in these helical 1D LPs are substituted with C3-symmetric 1,3,5-triformylphloroglucinol (TP), yielding the corresponding 2D network β-ketoenamine COFs. Crystallinity and helicity of the resultant β-ketoenamine COFs intimately hinge on reaction conditions, including the aldehyde stoichiometry of Tp and TPA, as well as the quantity and concentration of the catalyst employed. Under optimized conditions, the nucleation and growth were precisely governed, achieving a harmonious equilibrium of crystallinity and helicity within the generated 2D network β-ketoenamine COFs, even with covalent bond rupture, recombination, and topological transition (from [C2 + C2] to [C3 + C2]). Impressively, the ground state chirality inherent to helical 1D LPs seamlessly transfers to helical 2D network β-ketoenamine COFs. This study not only offers new perspectives on the development of chiral functional COFs, but also provides fresh insights into the precise control of COFs' microscopic morphology. [ABSTRACT FROM AUTHOR]

The jammed liquid‐liquid interface offers an elegant approach to achieve non‐equilibrium shapes of liquids. The interfacial jamming subsequently brings about formation of 2D "solid‐like" assembly. In this work, biphasic reaction between a perylenediimide based luminogen benzoperylenediimide monoanhydride (Bp(Im)2MA) and diamines are demonstrated that rendered amide bond formation and in turn amide nanoconjugates across the oil‐water interface. Amide nanoconjugates formed with different diamines showed diamine alkyl chain length dependent varied interfacial properties and sizes. Jamming of the interface is judiciously utilized to induce aggregation of amide nanoconjugates which successfully established macroscopic Aggregation Induced Emission‐switching (AIE‐switching) behavior. Further, the versatility of this approach is extended to analyze the reactivity of chiral amino acids. The reaction between the Bp(Im)2MA luminogen and chiral amino acids exhibits macroscopic enantioselectivity at jammed interface via diverse surface coverage of the amino acids‐based amide nanoconjugates. The formation of discrete nanoscopic amide interfacial assembly for each of the L‐ and D‐ amino acids isomers is corroborated with Atomic Force Microscopy (AFM) images. This study extends a fascinating pathway to aid in understanding and fabrication of structurally diverse jammed interfaces and aggregation of organic molecules across an oil‐water interface. [ABSTRACT FROM AUTHOR]

The chiral P,N,N‐ligands represented a new type of tridentate ligand developed in recent years and displayed wide utilities in asymmetric catalysis. In the past decades, numerous chiral P,N,N‐ligands with ferrocene, phenethylamine and spiro backbones were synthesized by addition of an aminopyridine, imidazole or diamines coordinating group. These chiral tridentate P,N,N‐ligands showed excellent performance in the ruthenium, iridium, manganese, or cobalt‐catalyzed asymmetric hydrogenations. A wide range of substrates, including simple ketones, α‐halogenated ketones, α‐hydroxy ketones, α‐ or β‐amino keto‐ ones, α‐, γ‐, or δ‐keto acids, α‐ or β‐keto amides, β‐ or δ‐keto esters, α‐ or β‐enones, olefins, imines, quinolines and indoles, could be hydrogenated to afford the corresponding chiral products with high yields and enantioselectivities. In this review, progress on the asymmetric hydrogenation of C=O, C=N, C=C bonds with chiral tridentate P,N,N‐ligands was summarized. [ABSTRACT FROM AUTHOR]

P‐stereogenic benzo‐fused heterocycles is a privileged skeleton due to their outstanding catalytic properties and bioactivities. However, their enantioselective synthesis is still underdeveloped. Here we demonstrate the use of easily accessible racemic H−P(O) compounds as starting materials and commercial chiral N1, N2‐dimethyl‐1,2‐diphenylethane‐1,2‐diamine ligand in combination with Cu(I) catalysts to enable an attractive dynamic kinetic C(sp2)−P cross‐coupling reaction. This protocol not only exhibits a broad substrate scope but also provides general access to a diverse range of useful P‐stereogenic five‐, six‐, seven‐ and eight‐membered benzo‐fused O, P‐ containing heterocycles with good to high yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

A bidentate boron Lewis acid based on 1,8‐diethynylanthracene has been studied in detail with respect to its adduct formation with diamines and diphosphanes of different linker lengths between the donor functions. A clear correlation between the linker length of the bifunctional base and the formation of 1 : 1 adducts, 1 : 2 adducts or oligomers was found. The adducts were characterized in solution by NMR titration experiments and structurally by X‐ray diffraction. In addition, adduct formation and competition experiments of the host system with ZR3 (Z=N, P; R=H, Me) demonstrated the generally higher stability of alkylphosphane adducts compared to alkylamine adducts with boron functions. The results provide a general insight into the adduct formation of bidentate Lewis acids with guests of different sizes as well as the differences in stability between borane‐amine and borane‐phosphane adducts. [ABSTRACT FROM AUTHOR]