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Context: Nickel-catalyzed hydroamination of dienes with phenylmethanamines was studied theoretically to investigate reaction mechanism. These calculated results revealed that Ni-catalyzed hydroamination began with the O − H bond activation of trifluoroethanol, including three important elementary steps: the ligand-to-ligand hydrogen migration, the nucleophilic attack of phenylmethanamine, and hydrogen migration. The nucleophilic attack of phenylmethanamine was the rate-determining step, and the branched product of 3,4-addition with (S)-chirality was the most dominant. The N − H bond activation of phenylmethanamine occurred more difficultly than the O − H bond of trifluoroethanol, because of high ΔG and ΔG≠. In addition, the origin of regioselectivity and enantioselectivity, and prediction of the ligand were also discussed in this text. Methods: All computations were performed with Gaussian09 program. All geometries were optimized at the ωB97XD/6-31G(d,p) level (SDD for Ni), and to obtain more accurate potential energy, single-point calculation was carried out at the ωB97XD/cc-pVDZ level (SDD for Ni). The Cramer-Truhlar continuum solvation model (SMD) was used to evaluate solvation effect of mesitylene, and a correction of the translational entropy was made with the procedure of Whitesides group. [ABSTRACT FROM AUTHOR]

The adopted healant has a significant impact on the final healing performance of self‐healing materials. Herein, the healant system, bisphenol‐F diglycidyl ether (BFDGE) and polytheramine JEFFAMINE T403, which possesses the capability of fully healing at room temperature (RT) for epoxy, was investigated in depth. The healing potential of this healant system and its healing benchmark after microencapsulation were systematically studied using a manual injecting method. It shows that the maximum and benchmark healing efficiencies respectively reach about 210% and 170% at RT for 48 h. The robustness of the cured healant was checked by studying the mechanical properties of BFDGE/T403. It verified that the tensile properties of the healant are stable after RT curing for 48 h. The curing degree of the healant was further characterized using differential scanning calorimetry by measuring the residual exotherm. It reaches 90% when the maximum healing performance is achieved and stabilizes at 95% thereafter. The results from the manually healing test, the tensile test, and the DSC test, are consistent with each other, which validate the robustness of BFDGE/T403 as healant for self‐healing epoxies. [ABSTRACT FROM AUTHOR]

The synthesis of tertiary amines from alcohols (i.e. heptanol, dodecanol, cyclohexanol, benzylalcohol) and secondary amines (Me2NH (DMA), nPr2NH, nBu2NH) has been achieved in one step using trimetallic nanoparticles (NPs) displaying a magnetic core (Co4Ni6 and Fe3Ni7) and a Cu shell as both catalysts and heating agent in the presence of an alternating magnetic field. This methodology limits the redistribution reactions occurring on amines at high temperature leading to both much higher conversion and selectivity in the absence of solvent than usually observed using conventional heating. Moreover, Co4Ni6@Cu NPs were found moisture resistant, thereby allowing for performing the reaction with commercial DMA in water (40 % wt) with again high conversion and selectivity. [ABSTRACT FROM AUTHOR]

A novel and efficient one‐pot method has been developed for the synthesis of thioamides through coupling reactions between thiocarbamoyl fluorides, which are generated in situ from amines, and boronic acids. The key to the success of this transformation lies in the use of nickel a catalyst combined with PCy3 as a ligand. This innovative reaction protocol provides mild reaction conditions suitable for producing a diverse array of thioamides, and the late‐stage modification of amoxapine was successfully achieved. [ABSTRACT FROM AUTHOR]

Herein, a microwave promoted tandem reaction of free primary arylamines with diazo compounds in water for clean synthesis of 2,2‐disubstituted 3‐oxindoles is present. Water plays important roles in the whole cascade process: O−H insertion to diazo, air oxidation, ortho C−H functionalization, cyclization and 1,2‐ester migration. In particular, water plays a mediation role in the site selective ortho‐C−H addition. [ABSTRACT FROM AUTHOR]

Reductive amination is a practical method for converting carbonyl compounds to amines. Using this reaction as an example, we introduce a comprehensive organic chemistry experiment designed for senior undergraduates: the reductive amination of isophthalaldehyde with silane to synthesize m-xylylenediamine. In this reaction, tert-butyl carbamate (BocNH2) serves as the nitrogen source, and triethylsilane (Et3SiH) acts as the reducing agent, with trifluoroacetic acid as the catalyst. Isophthalaldehyde undergoes reductive amination to produce Bocprotected m-xylylenediamine, which is subsequently deprotected to yield m-xylylenediamine hydrochloride. The final product, m-xylylenediamine, is obtained by treating the hydrochloride salt with sodium hydroxide. The experimental procedure includes techniques such as extraction, vacuum distillation, drying, recrystallization, and melting point determination, along with analytical methods like thin-layer chromatography (TLC), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) spectroscopy. This synthetic route is well-suited for laboratory synthesis, providing high yields and easy purification of the product. The experiment enhances students' skills in organic synthesis and deepens their understanding and application of spectroscopic techniques. [ABSTRACT FROM AUTHOR]

Bisfunctional benzoxazine and polyether diamine‐based polymers show Arrhenius‐like stress‐relaxation varying with stoichiometry and polymerization temperatures proving vitrimeric behavior. Molecular structural investigations reveal the presence of different aminoalkylated phenols occurring at varying ratios depending on polymer composition and polymerization conditions. The vitrimeric mechanism is found to involve an amine exchange reaction of aminoalkylated phenols in an equilibrium reaction like a nucleophilic substitution reaction. As determined by molecular studies and dissolution experiments in reactive solvents, aliphatic and aromatic primary as well as aliphatic secondary amines in the polybenzoxazine structure can act as nucleophiles in reaction with electrophilic methylene bridges. Thus, aminoalkylated phenols proved to be a relevant structural motif resulting in a vitrimeric polybenzoxazine due to amine exchange reaction. [ABSTRACT FROM AUTHOR]

Reduction of carboxamides is an efficient approach to obtain the corresponding amines, albeit it is one of the most problematic. In this work, by use of pinacolborane (HBpin) as a reductant, the rare‐earth metal tris (arylamido) complex supported by a ferrocenyl‐modified arylamido ligand La[NH‐2,6‐iPr2‐4‐FcC6H2]3 was employed as a precatalyst for primary and secondary amide reductions. This catalyst system exhibited high activity toward hydroborative reduction of amides to amines under mild conditions, as well good tolerance for heteroatoms and functional groups in the reduction. A lanthanide hydride was experimentally verified as the active species and the reduction mechanism was proposed. [ABSTRACT FROM AUTHOR]

CO2 separation technology at low pressure is most desirable in carbon capture projects to mitigate global warming. Facilitated transport membranes offer selective and effective CO2 permeation using a wide range of carbon carriers at low pressure. Porous fillers were recently included as they can carry abundant fixed carriers besides offering open channels for CO2 permeation. This study investigates the effects of amine‐modified zeolitic imidazolate framework‐8 (ZIF‐8) with well‐defined micropores and gas sieving ability in polyvinyl alcohol (PVA) membranes containing an ionic liquid that worked as mobile carriers. The effects of amine‐modified ZIF‐8 and silica nanoparticles on membrane properties and separation performance were also compared. Fourier transform infrared spectra confirmed the incorporation of ZIF‐8, secondary amine, IL anions, and silica nanoparticles in PVA membranes. Energy dispersive analysis showed the good dispersion of inorganic fillers. The amine‐modified silica nanoparticles resulted in higher thermal stability compared to the amine‐modified ZIF‐8 in PVA membranes containing [bmin][Ac] ionic liquid, as shown in the thermogravimetric analysis. However, the CO2 separation performance of PVA membranes containing [bmim][Ac] ionic liquid was improved more significantly by the amine‐modified ZIF‐8 with microporous structure. A CO2/N2 ideal selectivity of 85.65 and CO2 permeance up to 4,502.91 GPU were attained. Unlike the CO2/N2 ideal selectivity, the CO2 permeance was not significantly affected either using [bmin][Ac] or [bmin][BF4]. The humid gas greatly enhanced the CO2 permeance without much changes in the CO2/N2 ideal selectivity due to the promotion of facilitated transport. © 2024 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A novel metal‐organic frameworks (MOF) material, namely {Zn3(bpybc)(imdc)2·H2O)}n (1), (bpybc2− = 1,1′‐bis(4‐carboxyphenyl)‐4,4′ ‐bipyridinium cation, imdc3− = 4,5‐imidazole‐dicarboxylic acid anion) has been successfully synthesized under solvothermal conditions. The synthesis utilized H2bpybc·2Cl, 4,5‐imidazole‐dicarboxylic acid and Zn(NO3)2·6H2O as the raw materials. Complex 1 not only exhibits reversible photochromic behavior but also features photocontrolled luminescence properties. Notably, complex 1 shows the sensing ability of Cr2O72−. It has the capability to selectively detect ammonia vapor, undergoing a color change from orange to tan in response to ammonia vapors, thereby exhibiting certain sensing properties for ammonia vapor. [ABSTRACT FROM AUTHOR]

The complexes [RuCl(Cy)(NH2Ph)2]Cl (1), [RuCl2(Cy)(NH2Bz)] (2), and [RuCl2(Cy)(NHBz2)] (3) were synthesized under identical conditions from [RuCl2(Cy)]2, where Cy=η6‐p‐cymene, Ph=phenyl, and Bz=benzyl. X‐ray crystallography revealed an additional NH2Ph ligand in 1, distinguishing it from the neutral mono‐amine complexes 2 and 3. The number of amines in these complexes did not correlate clearly with the σ‐donor character or steric hindrance of the amines. Different reactivities were observed for the ROMP of norbornene (NBE), as measured by batch reactions and kinetic studies using Raman and 1H NMR spectroscopy. Semiquantitative conversions reached up to 90 % with complex 1 and around 40 % with complexes 2 and 3. DFT calculations supported the hypothesis that the reaction for complex 1 involves the release of an amine through a dissociative mechanism, whereas complexes 2 and 3 react through an associative mechanism involving amine loss. The presence of an amine in the propagation species of complex 1 suggests the participation of the amine as an ancillary ligand. All carbene species are of the η2‐p‐cymene type, and the catalytic cycle follows a 14–16‐14 electron counting mechanism. [ABSTRACT FROM AUTHOR]

The chemistry of bidentate ligands with a dppf-like motif, where phosphorus is fully or partially replaced by other pnictogens as donor sites, is summarized and discussed in this comprehensive review, while covering the literature from 1966 to 2024, related to more than 165 original references and discussing more than 75 independent chemical entities (1–41). Besides addressing synthetic, structural, and electrochemical aspects of such compounds, their donor properties and metal coordination behavior is discussed, along with catalytic applications. Based on their electronic and steric situations, trends in the performance of such compounds, either as ligands for catalysis or on their own merits for non-catalytic purposes, have been elucidated. Related topics that could not be covered in this article have been acknowledged by referring to the literature for completeness. [ABSTRACT FROM AUTHOR]

New amino-derivatives of 3-oxo-24-nor-allobetulin (3-semicarbazone, 1,2,3-thiadiazole, 3β-amine, methoxylactam) were synthesized. The structures of the 3E-oxime and 3E-methoxyoxime of 24-nor-allobetulin were confirmed by X-ray crystal structure analyses. [ABSTRACT FROM AUTHOR]

There are many harmful chemicals in the wood protection and coating industry. These substances adversely affect human health over time and cause many diseases such as respiratory tract, skin, or lung cancer over time. In this study, bio-based nano-coatings as a replacement of bisphenol-A (BPA) were prepared by both protecting the wood organically and trying to prevent applications that would adversely affect human health. This study was aimed to improve wood properties such as oven and air-dry densities and water absorption (WA) from physical properties, color, gloss, and roughness from surface properties after natural weathering, and compression strength parallel to the grain (CSPG) from mechanical properties by coating these materials on Oriental beech wood. New bio-based epoxide–amine (EP) coatings were preferred over BPA material and their nano-composite coating derivatives including fullerenes, graphene, and carbon nanotubes were prepared by reactions of epoxy-functionalized tung. A diamine hardener (isophorone diamine) and epoxide tung oil (ETO) doped with nanoparticles were cured, and their physical properties were also determined. Consistent with our previous work, glycidyl methacrylate and tung oil were preferred to form epoxy-functionalized tung oil (ETO) by opting for a Diels–Alder reaction. The new bio-based epoxide–amine-cured systems were created at ambient temperature using a 1:1 epoxy-to-amine molar ratio. The specimens covered with epoxide nano-composites exhibited greater water resistance than the control group. When the surface properties of the epoxy nano-composite-coated specimens after weathering were examined, a more stable color change was observed compared to the control group. Furthermore, while the glossiness of the epoxide nano-composite-coated specimens decreased more than the control group, their roughness increased more. CSPG of epoxy-coated specimens increased a little bit compared to the control group, but no statistical difference was found. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of monovalent and divalent ions and the dosage of a SiO2-based nanocomposite on the thermochemical stability of HPAM polymeric solution. Chelating amine–functionalized NPs (AFNPs) were used to enhance the thermochemical stability of HPAM based on capturing monovalent/divalent ions after seven days at 70°C. Different polymer solutions prepared with calcium chloride dihydrate (CaCl2·2H2O) at 2000 mg/L and sodium chloride (NaCl) at 10000 mg/L, and two different dosages of HPAM (1000 and 2000 mg/L) were assessed in the presence and absence of AFNPs at dosages of 200, 500 and 1000 mg/L. The nanocomposite was characterized by N2 adsorption, Fourier-transformed infrared spectrophotometry (FTIR), thermogravimetric analysis (TGA), dynamic Light Scattering (DLS), and Zeta potential (ZP). Stability tests over time confirmed the positive effect of nanocomposite on increasing the thermochemical stability of polymer solutions. Results revealed that adding 0, 200, and 500 mg/L of nanocomposite to the polymeric solution at 1000 mg/L of HPAM, 10000 mg/L of NaCl, and 2000 mg/L of CaCl2·2H2O led to the viscosity reductions of 73.5%, 18%, and less than 1% after 7 days (70°C), respectively. Nanocomposite at 200 mg/L reduces the polymer degradation in the presence of the two salts evaluated separately, i.e., 20% for 10000 mg/L of NaCl and 15% for 2000 mg/L of CaCl2·2H2O. The adsorption tests on AFNPs and SiO2 NPs concluded that AFNPs had higher adsorption of cations in comparison to SiO2 NPs and that greater adsorption of cations is related to a reduction in polymer degradation.

Treatment of various (R)-N-(2,2,3,3-tetrafluoropent-4-en-1-ylidene)-1-phenylethylamine derivatives with 2.4 equiv of DBU in toluene at room temperature to 50 °C for 24 h led to a smooth [1,3]-proton shift reaction with a high chirality transfer, affording the corresponding rearranged products in acceptable yields. Without purification, these products were subjected to acid hydrolysis and the subsequent N-Cbz protection, providing the optically active tetrafluoroethylenated amides in moderate three-step yields.

Abstract This study developed a novel and highly active heterogeneous catalyst of nickel nanoparticles supported on β-cyclodextrin-grafted magnetic Fe3O4 nanoparticles (Ni@β-CD@Fe3O4). β-CD, a biodegradable, biocompatible, green, and non-toxic cyclic oligosaccharide, was modified with Fe3O4 nanoparticles to create β-CD@Fe3O4. The nickel was then immobilized onto this support. The catalyst was characterized using FT-IR, XRD, TEM, AAS, FE-SEM, TGA, EDX, DRS-UV-Vis spectra, and VSM techniques. The catalytic activity of Ni@β-CD@Fe3O4 was evaluated for the reduction of nitroarene compounds in water at 25 ℃. This nanocatalyst indicated great activity and selectivity in reducing various nitroarenes, including nitrobenzene, nitroaniline, nitrotoluene, and nitrophenol derivatives. Additionally, the catalyst showed significant reusability and could be easily separated using an external magnet, highlighting its potential for green chemistry and sustainable industrial applications.

Coordination compounds of polydentate nitrogen ligands with metals are used extensively in research areas such as catalysis, and as models of complex active sites of enzymes in bioinorganic chemistry. Tris(2-pyridylmethyl)amine (TPA) is a tripodal tetradentate ligand that is known to form coordination compounds with metals, including copper, iron and zinc. The related compound, tris[(6-bromopyridin-2-yl)methyl]amine (TPABr3), C18H15Br3N4, which possesses a bromine atom on the 6-position of each of the three pyridyl moieties, is also known but has not been heavily investigated. The molecular structure of TPABr3 as determined by X-ray diffraction is reported here. The TPABr3 molecule belongs to the triclinic, P\overline{1} space group and displays interesting intermolecular Br...Br interactions that provide a stabilizing influence within the molecule.

Silica and silicate scale deposition in the production systems resulted in reduced production rates and equipment damages. Chemical scale inhibition using squeeze method is advantageous for petroleum reservoir conditions. This paper aims to assess the adsorption and squeeze performance of developed scale inhibitors that consist of polyamidoamine (PAMAM) dendrimers and pteroyl-L-glutamic acid (PGLU). Commercial inhibitor, diethylenetriamine penta(methylene phosphonic acid), also known as DETPMP, was also used to benchmark the laboratory findings. Static adsorption test and core flooding were performed to investigate the adsorption characteristics and retention of the inhibitors in Berea sandstone cores. Simulation was also conducted to estimate the squeeze performance of the inhibitors. Results revealed that PAMAM-2-PGLU scale inhibitor exhibited the highest adsorption and retention in the sandstone core. The treatment of PAMAM-2-PGLU and PAMAM-1-PGLU inhibitors increased the core permeabilities. SQUEEZE IV model predicted that both PAMAM-PGLU inhibitors yielded longer squeeze lifetime than DETPMP inhibitor. Both experimental and simulation results showed good fit in terms of adsorption and squeeze lifetime. In this paper, the tested PAMAM-PGLU scale inhibitors have demonstrated better adsorption, retention, and squeeze lifetime in sandstone formation. They could offer effective and low-toxicity alternatives to commercial inhibitors due to raising environmental concerns.

Purine stretches, sequences of adenine (A) and guanine (G) in DNA, play critical roles in binding regulatory protein factors and influence gene expression by affecting DNA folding. This study investigates the relationship between purine stretches and cancer development, considering the aromaticity of purines, quantified by methods like Hückel's rule and NICS calculations, and the importance of the flanking sequence context. A pronounced avoidance of long purine stretches by typical cancer mutations was observed in public data on the intergenic regions of cancer patients, suggesting a role of intergenic sequences in chromatin reorganization and gene regulation. A statistically significant shortening of purine stretches in cancerous tumors (p value < 0.0001) was found. The insights into the aromatic nature of purines and their stacking energies explain the role of purine stretches in DNA structure, contributing to their role in cancer progression. This research lays the groundwork for understanding the nature of purine stretches, emphasizing their importance in gene regulation and chromatin restructuring, and offers potential avenues for novel cancer therapies and insights into cancer etiology. [ABSTRACT FROM AUTHOR]

Integrated carbon capture and utilization (ICCU) simplifies the CO2 utilization process by converting chemically combined CO2 molecules into value-added chemicals, leading to a strong energy-saving effect by omitting the CO2 separation process. Two reaction routes for the hydrogenation of amine captured CO2 to methanol over heterogeneous catalysts were summarized: alcoholic hydroxyl groups-promoted CO2 hydrogenation process over Cu or Pd-based catalysts via formate and ester route, and methanol production from the direct hydrogenation of formate over Au-based catalyst. The technical effectiveness of concurrent carbon capture with heterogeneous catalysis toward methanol via alcoholic hydroxyl groups-promoted CO2 hydrogenation is similar to that of the gas-phase CO2 hydrogenation to methanol over heterogeneous catalysts. The sintering of the catalysts, the phase change of the supports, the combination of amines and the catalysts (namely leaching), and the reaction of water with the supports can cause a decrease in the performance of the catalysts. Thus, it is important to rationally design next-generation stable catalysts to achieve amine captured CO2 hydrogenation to methanol while at the same time regenerating amines. The development of heterogeneous catalysts for methanol synthesis in the liquid phase and the development of the CO2 capture process for subsequent conversion(1 ~ 70%) were carefully reviewed. The integration and optimization of multi-pollutant efficient removal technology, selectively coupled CO2 capture technology, and selective routes for methanol synthesis can achieve industrial verification in typical power plants, which is of great significance in promoting energy conservation, emission reduction, and low-carbon footprint. [ABSTRACT FROM AUTHOR]

The conventional use of polyurethane in various applications is hindered by significant challenges, such as toxicity concerns, moisture sensitivity, and environmental impact. In response, there has been a notable surge in research focusing on bio-based alternatives, particularly non-isocyanate polyurethanes (NIPUs), aligning with sustainable development objectives. NIPUs offer a promising solution by eliminating the need for isocyanates, employing cyclic carbonates and diamines instead. Out of various sources available, non-traditional vegetable oils present a viable starting material for cyclic carbonate synthesis due to their availability, renewability, and affordability. However, despite the growing interest in NIPUs, there remains a scarcity of literature on the utilization of non-traditional oils for their development. This short review aims to fill this gap by providing an overview of bio-based NIPUs synthesized from non-traditional vegetable oils such as jatropha oil, castor oil, lignin oil, linseed oil, and rubber seed oil. The review covers the synthesis methods of NIPUs via polyaddition reactions of carbonates and amines, detailing properties, advantages, and applications of each oil-based NIPU. Furthermore, by identifying research gaps and proposing potential solutions, this paper aims to encourage researchers to consider non-traditional oils for NIPU synthesis, facilitating significant advancements in the field. [ABSTRACT FROM AUTHOR]

Compared to modifications at the molecular periphery, skeletal adjustments present greater challenges. Within this context, skeletal rearrangement technology stands out for its significant advantages in rapidly achieving structural diversity. Yet, the development of this technology for ring contraction of saturated cyclic amines remains exceedingly rare. While most existing methods rely on specific substitution patterns to achieve ring contraction, there is a persistent demand for a more general strategy for substitution‐free cyclic amines. To address this issue, we report a B(C6F5)3‐catalyzed skeletal rearrangement of hydroxylamines with hydrosilanes. This methodology, when combined with the N‐hydroxylation of amines, enables the regioselective ring contraction of cyclic amines and proves equally effective for rapid reorganization of acyclic amine skeletons. By this, the direct scaffold hopping of drug molecules and the strategic deletion of carbon atoms are achieved in a mild manner. Based on mechanistic experiments and density functional theory calculations, a possible mechanism for this process is proposed. [ABSTRACT FROM AUTHOR]

A convenient synthetic protocol for diverse 4, 5-disubstituted-6-methyl-2-(methylthio)pyrimidines was successfully developed by Sonogashira reactions. In the presence of Pd-Cu catalysts, one-pot, multi-step reaction of amines, terminal alkynes, and 4-chloro-5-iodo-6-methyl-2-(methylthio)pyrimidine in DMF at 80°C resulted in 4, 5-disubstituted-6-methyl-2-(methylthio)pyrimidine derivatives in moderate to good yields. [ABSTRACT FROM AUTHOR]

Combining simple amines with the bench‐stable sulfinylamine Tr‐NSO allows in situ preparation of reactive alkyl sulfinylamines, which when combined with alkyl radicals generated by photocatalytic decarboxylation, provides N‐alkyl sulfinamides. The reactions are broad in scope and tolerate a wide variety of functional groups on both the acid and amine components. The sulfinamide products are used to prepare a selection of challenging S(VI) products. The method provides a convenient way to use reactive and unstable alkyl sulfinylamines. [ABSTRACT FROM AUTHOR]

Porphyrins‐based porous organic polymers (POP) were widely used in photocatalytic oxidation under visible light owing to their superiority in the activation of oxygen. In contrast, the efficiency is usually limited due to the fast recombination and slow electron transfer. Herein, we report the use of a trioporphyrins‐based covalent triazine framework (Por‐CTF) as visible‐light‐active photocatalyst for the coupling oxidative of amines to imines at room temperature. By incorporating the π‐conjugated porphyrin building block led to the enhanced electron transport between molecules, and the extended recombination time of excited electrons. The photocatalytic efficiency of Por‐CTF is superior to that of polymer in absence of triazine framework (POP‐TSP), which was prepared by radical polymerization using tetra‐(4‐vinylphenyl) porphyrin (TSP) as monomer. Por‐CTF catalyst presented excellent efficiency for various primary amines and stability. This work provides a reasonable guidance of catalyst molecular structure design for enhancing efficiency in the photocatalytic oxidation. [ABSTRACT FROM AUTHOR]

A highly effective approach has been proposed for the synthesis of unique imidazole aniline compounds via a reaction sequence including acylation of substituted anilines with 2-chloroacetyl chloride, alkylation of 2-butyl-5-chloro-1H-imidazole-4-carbaldehyde with the resulting 2-chloroacetanilides, and con-densa-tion of 2-(2-butyl-5-chloro-4-formyl-1H-imidazol-1-yl)-N-(substituted phenyl)acetamides with 4-{4-[5-(amino-methyl)-2-oxo-1,3-oxazolidin-3-yl]phenyl}morpholin-3-one. The newly synthesized compounds have been screened for their in vitro antimalarial potential against Plasmodium falciparum and found to exhibit incredibly impressive half-maximum inhibitory concentration (IC50) values. Molecular docking has been performed for the most active compound and dihydrofolate reductase–thymidylate synthase (DHFR-TS) from the wild-type Plasmodium falciparum, and hydrogen bond interactions between the amino acid residues Ser167 and Ser111 and azomethine and imidazole nitrogen atoms, respectively, have been revealed. [ABSTRACT FROM AUTHOR]

Development of elegant, selective, and efficient strategies for the production of value‐added platform chemicals from renewable feedstocks are in high demand to achieve the future needs and sustainable goals. In this context, an efficient acid‐promoted synthesis of highly valuable hydroxymethylfurfural (HMF) has been demonstrated from glucose, a major constituent of lignocellulosic biomass. The major challenge in the conversion of glucose to HMF is the selective isomerization of glucose to ketose, which in the present work has been successfully addressed through the amine‐mediated rearrangement of glucose to aminofructose under Amadori rearrangement. Importantly, subsequent dehydration step affords HMF and regenerates the amine employed in the first step, which could be readily recovered. In addition, scale‐up and successful integration into one‐pot synthesis of HMF proves the efficiency and applicability of the present transformation in large scale application. In addition, the method was also successfully extended to other monosaccharides and disaccharides to produce HMF. [ABSTRACT FROM AUTHOR]

This study aims to analyze the degradation behavior and mechanisms of amine-cured epoxy asphalt (EA) under the combined effects of ultraviolet (UV) radiation, oxygen, and temperature. To achieve this, amine-cured epoxy resin (ER) and EAs containing 35%, 45%, and 55% asphalt content were prepared and subjected to simulated UV-based aging. Various analytical techniques were employed to investigate the mechanical properties, microstructure, morphology, and oxidation layer of ER and EAs. The results indicate that after UV-based aging, ER and EAs with 35%–45% asphalt content experienced an increase in mass, a decrease in strength and glass transition temperature. In comparison, EAs with 55% asphalt content exhibited the opposite trends. The elongation and (Tanδ)max of ER and EAs reduced, whereas the storage modulus and hardness at mid to high temperatures rose. At the microstructural level, the degradation of the resin phase was confirmed by changes in ether, ester, and amide groups, whereas the generation of sulfoxide groups was associated with the oxidation of the asphalt phase. Compared with ER, the surface of EA has obvious defects after aging, which is the main reason for the decrease in contact angle. As the asphalt content increases, EAs exhibit higher carbonyl concentration, more profound oxidation, and more obvious performance degradation. This trend suggests that the resin phase mitigates the aging of the asphalt phase by absorbing harmful UV radiation and oxygen. [ABSTRACT FROM AUTHOR]

Two novel viologen-functionalized Supramolecular compounds {[H2bpybc]0.5⋅[H2BTEC]0.5⋅ H2O}n (1) and {[H2bpybc]⋅[H3BTEC]2⋅2H2O}n (2), were synthesized through a solution-based approach in the presence of 1,1'-bis((4-carboxybenzyl)-4,4'-bipyridine) chloride (H2bpybc⋅2Cl), 1,2,4,5-benzenetetracarboxylic acid (H4BTEC), and Zn(NO3)2⋅6H2O. Single crystal X-ray diffraction analysis showed the three-dimensional supramolecular network structures within compounds 1 and 2. Notably, these compounds exhibit reversible photochromism due to the formation of viologen radicals, facilitating electron transfer. The order of light response time follows the sequence 1 > 2. To further elucidate the discoloration mechanism, Time dependent density functional theory (TDDFT) was employed. Additionally, compound 1 showed interesting photomodulated fluorescence behavior. Faster responsive rate is observed in the system of 1 due to its shorter D–A distance and intramolecular hydrogen bonding structure. Remarkably, compound 1 displays selective sensing capabilities towards NH3 and triethylamine among various organic amines. Given its photochromic properties, compound 1 holds promise as a potential candidate for photochromic materials, anti-counterfeit paints, and information monitoring technology applications. [ABSTRACT FROM AUTHOR]

Mixed-ligand complexes of Pd(II) and Pt(II) with 2H-benzo[e][1,3] oxazine-2,4(3H)-dione (HBzoxe), tertiary phosphines (dppe, dppp, dppf and Ph3P), 2,2′-bipyridine (Bipy) and 1,10-phenanthroline (Phen) have been synthesized and characterized by molar conductance measurements, elemental analysis, IR and NMR (1H, 13C and 31P) spectroscopy. In addition, the antimicrobial activity assay studies. The results showed that the HBzoxe ligand behaves as a bidentate chelation ligand through the O and N atoms in [M(Bzoxe)2] {MII = Pd(1) and Pt(2)} complexes, whereas it acts as monodentate ligand through the oxygen atom in complexes (3–14) to afford a square planner geometry around Pd(II) and Pt(II) for all of the complexes. All of the complexes were moderately active on all the bacteria tested (Staphylococcus aureus and Escherichia coli). Hirshfeld surface analysis was carried out to investigate the cooperative non-covalent supramolecular interactions within the various complexes. [ABSTRACT FROM AUTHOR]

The N‐methylation reaction of amines with methanol via the borrowing‐hydrogen strategy is an important method for the construction of C−N bonds. Compared with other C1 sources, such as toxic formaldehyde or expensive formic acid, methanol is more suitable for N‐methylation reactions due to its eco‐friendliness and low price. Using this strategy, various types N‐methylated products, including biological and pharmaceutical molecules have been prepared. Here, we present a thorough survey of decades of articles showing current developments in N‐methylation reactions with methanol. We discuss homogenous, heterogenous and light‐driven catalytic systems for both N‐methylation and N,N‐dimethylation reactions. This review presents the shortcomings of current developments and provides future development progress in N‐methylation reactions with methanol. [ABSTRACT FROM AUTHOR]

In this study, the high potential tertiary N-methyl-4-piperidinol or MPDL (0.25–1.00 M) was blended with 5 M monoethanolamine (MEA) to formulate 5.25–6.00 M MEA-MPDL solvent and compare with the benchmark 5 M MEA. It was found that the density and the Henry's constant slightly decreased, while the viscosity increased as the MPDL concentration in the blend increased. Even though the equilibrium CO2-loaded viscosity considerably increased (by 34.3–40.2%) as the MPDL content increased, it was still in a great operating region of less than 10 mPa.s. Experimental overall reaction kinetics constant ( k ov ) was well corresponding with the zwitterion mechanism of MEA and the base-catalyze hydration mechanism of MPDL based absorption kinetics model, with %AAD of 0.56%. Interestingly, an addition of MPDL into 5 M MEA slightly enhanced k ov (1.2–3.3% increment) and considerably favored absorption capacity (13–31% elevation), and regeneration heat duty (28–47% reduction), respecting 5 M MEA. The proposed strategic blending can maintain the overall solvent reactivity at the same level of the benchmark, while obviously increase the absorption capacity and largely reduce the regeneration heat duty. This highly favors a solvent upgrading for the existing 5 M MEA based CO2 capture plant. According to the recent data, 5 M MEA + 1.00 M MPDL was suggested. Since the blend was formulated at high concentration, its corrosiveness should also be considered. [ABSTRACT FROM AUTHOR]

In drilling, mitigating wellbore instability issues in reactive shale formations is crucial and takes top priority. These instabilities often lead to significant disruptions in drilling operations, resulting in loss of time and increased operational costs. This study is aimed at mitigating these challenges, with a primary focus on reducing filtration loss volume and enhancing wellbore stability within shale formations. In this study, the filtration properties of water-based mud along with Ranikot shale stability were investigated in presence of PAC and Amine. In this revolutionary study, the synergistic effect of two additives on the filtration properties of water-based mud and Ranikot shale was comprehensively investigated and visualized through 3D surface plots. A total of 13 distinct mud samples were meticulously formulated using Central Composite Design, a pivotal subset of response surface methodology. The result of the study shows that there were no drastic variations in the mud weight recorded with changes in concentration of PAC and amine. Moreover, sample 4 with least concentration of both additives demonstrates a highest fluid loss volume of 13.5 mL/30 min, which highlights the importance of optimal concentration of PAC and amine in WBM. Furthermore, this low concentration sample formed a mud cake with rough and thick texture, exhibiting a high permeability of 0.54371 µD. In contrast, samples with high concentrations were extremely successful in maintaining a low fluid loss volume and forming a dense and compacted mud cake. Additionally, the combined influence of these particle on enhancing the hydrophobic behavior of the shale sample was also investigated. Sample 4 with least particles concentration demonstrated a contact angle of 37.398°, while the highest contact angle of 86.792° was exhibited by sample with greater concentration of amine and PAC. The result showed that the high concentration of PAC and amine in the mud sample led to a substantial enhancement of the shale hydrophobic character. This shows that when PAC and amine interact with the shale pellets it reduces the affinity for water and thereby increases its resistance to water ingress, which play a pivotal role in wellbore stability. The study's outcomes underscore the remarkable efficacy of PAC and amine in considerably reducing the filtrate loss, thereby leading to enhanced drilling efficiency and operational performance. [ABSTRACT FROM AUTHOR]

Herein, we disclose a new strategy that rapidly and reliably incorporates bromine atoms at distal, secondary C(sp3)−H sites in aliphatic amines with an excellent and predictable site‐selectivity pattern. The resulting halogenated building blocks serve as versatile linchpins to enable a series of carbon‐carbon and carbon‐heteroatom bond‐formations at remote C(sp3) sites, thus offering a new modular and unified platform that expediates the access to advanced sp3 architectures possessing valuable nitrogen‐containing saturated heterocycles of interest in medicinal chemistry settings. [ABSTRACT FROM AUTHOR]

We have developed a one-pot, four-component synthetic approach utilizing 5-sulfosalicylic acid dihydrate (5-SSA.2H2O) as an organocatalyst, enabling the synthesis of polyfunctional 3-pyrrolin-2-one molecules by employing dialkylacetylenedicarboxylate, amines, and either formaldehyde or aromatic aldehydes at room temperature. This approach presents numerous notable benefits such as shorter reaction time, simple and eco-friendly procedure, excellent yield, broad applicability across various substrates, and the use of a cost-effective, easily accessible and biodegradable catalyst. The structures of the 3-pyrrolin-2-one molecules were confirmed using techniques such as FTIR, 1HNMR, 13CNMR and HRMS. Overall, this study demonstrates a promising method for producing environmentally friendly polyfunctional 3-pyrrolin-2-one efficiently and smoothly at ambient temperature. [ABSTRACT FROM AUTHOR]