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The surface of titanium foil can be modified by heating in the air, in a N2 flow, and in an NH3 flow. Upon heating in the air, the elemental Ti gradually transforms to Ti3O at 550 °C and to rutile TiO2 at above 700 °C. Treatment in a N2 flow leads similarly to Ti3O at 600 °C and TiO2 at 700 °C, although the overall reaction is slower. Meanwhile, nitridation in the N2 flow is minimal, even at 900 °C. Heat treatment in an NH3 flow produces nitride phases through the ammonolysis of the hexagonal Ti. With an ammonolysis at 900 °C, trigonal Ti2N and cubic TiN form together while, at higher temperatures, TiN is dominant. The TiN layer can also be obtained via the ammonolysis of the TiO2 coating, that is, by the sequential treatments of Ti in the air and then in an NH3 flow. The titanium nitride layers have particulate microstructures and varying degrees of porosity, depending on the ammonolysis temperature and time. The TiO2-derived TiN has a significantly higher capacitance than TiN derived directly from Ti. The optimally prepared TiN specimen exhibits an areal specific capacitance of 66.2 F/cm2 at 0.034 mA/cm2. [ABSTRACT FROM AUTHOR]

Integration of hydrophobic and antibacterial functionalities into polyester‐cotton blended (PTCO) textiles has attracted more attention but remains a challenge. Here, a Janus fabric with antibacterial effect, hydrophobicity, and enhanced moisture‐permeability is fabricated using a "mist polymerization" approach. The PET fibers in the PTCO fabric are amino‐functionalized through ammonolysis reactions of PET molecules with HDA, and mist treatments of poly lauryl methacrylate (PLMA) and poly(DMC‐co‐MA) (PDM) are applied on the two side surfaces of the PTCO‐HDA fabric, respectively. The resulting Janus fabric exhibits an antibacterial rate of 99.9% against both E. coli and S. aureus, along with a hydrophobic property on its single side (PTCO‐HDA@PLMA). Additionally, the establishment of a surface‐free energy gradient across the fabric confers superior moisture‐permeability to the Janus fabric, offering advantages in preserving textile comfort. Moreover, this approach does not significantly compromise the original fabric properties, such as mechanical strength, moisture permeability, and fabric softness. The proposed method offers a straightforward and scalable strategy for textile finishing, demonstrating great potential in expanding the application scope of PTCO fabrics, and it may hold a pivotal role in diverse applications, notably encompassing home textiles, wound dressings, and high‐performance sportswear. [ABSTRACT FROM AUTHOR]

Compositionally complex transitional metal nitrides are possible candidates for ultra‐high temperature usage and are known for their superior properties due to the high configuration entropy. It is often difficult to synthesize pure metal nitrides in bulk, due to significant oxygen contamination; hence, they are synthesized mainly as thin films through magnetron sputtering, chemical vapor deposition or surface nitridation of high entropy alloys. The present article reports on a single‐phase compositionally complex ceramic, i.e., (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)NxC1−x, that is synthesized for the first time by employing an organometallic precursor route and using a double ammonolysis process. A multidisciplinary approach is performed to study these compositionally complex nitride and carbonitride systems, including experimental and theoretical investigations. [ABSTRACT FROM AUTHOR]

Copyright of Refractories / Naihuo Cailiao is the property of Naihuo Cailia (Refractories) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Common precursors for carbon materials typically include petroleum‐based polymers or MOF materials. However, these materials often encounter challenges such as metal aggregation, high cost, and metals leaching. In this work, a novel of approach lignin‐metal supramolecular framework complex (MSF@Lignin) is introduced. These complexes are formed through oxidative ammonolysis of lignin (OAL) to synthesize a nitrogen‐doped carbon‐encapsulated CoRu nanocatalyst (CoRu@OALC) via in situ carbonization. CoRu@OALC exhibited exceptional performance in both HER (90 mV) and OER (200 mV) at the current density of 10 mA cm−2, with an overall water splitting voltage of 1.5 V and outstanding stability under high density. During the pyrolysis process, metal became encapsulated by lignin‐derived carbon, occurring within the temperature range of 600–700 °C. In the catalytic process, active sites are primarily located within the defects in lignin‐derived carbon, showcasing a unique "self‐healing" phenomenon within the carbon layer. Oxygen‐containing intermediates (*OH, *O, and *OOH) facilitated the reconstruction of defects on the carbon layer, while the hydrogen‐containing intermediates (*H) contributed to the reappearance of a defect‐rich structure. [ABSTRACT FROM AUTHOR]

We report a novel chemical methodology for the synthesis of nanocrystalline CoWN2 which is stabilized by the induction effect. The methodology involves the nitridation of sol-gel-derived CoWO4 precursor in nanocrystalline form using gaseous NH3(g). We could obtain CoWN2 as a nitrided product at both 700 °C and 750 °C with varied crystallinity. The synthesized materials were characterized using XRD, FESEM, EDS, and magnetic measurements. XRD studies confirm hexagonal CoWN2 phase formation with a minor impurity phase which comprises of metallic Co. We have noted the values of lattice constants of CoWN2 materials, i.e., a = 2.876(7) Å, b = 2.876(6) Å, c = 15.372(48) Å, and a = 2.872(3) Å, b = 2.872(2) Å, and c = 15.381(21) for the products synthesized at 700 °C and synthesized at 750 °C, respectively. The crystallite sizes are calculated as 11 ± 0.5 nm for CoWN2 nanomaterials synthesized at 700 °C whereas 16 ± 0.5 nm for CoWN2 nanomaterials synthesized at 750 °C. FESEM micrograph studies of CoWN2 nanomaterials show nearly spherical particles. The average particle sizes obtained from FESEM images are 90 ± 5 nm for the nanomaterials obtained at 700 °C and 45 ± 2 nm for those obtained at 750 °C. Room temperature magnetic parameters, i.e., Ms and Hc for CoWN2 materials synthesized at 700 °C are found to be 1.49 emu/g and 389 Oe, respectively, whereas for CoWN2 materials (synthesized at 750 °C), the values marginally reduce to 0.06 emu/g and 375 Oe, respectively. [ABSTRACT FROM AUTHOR]

Cobalt molybdenum nitrides can be obtained from the oxidic precursor by reaction with gaseous ammonia. Despite the large number of works regarding the catalytical properties of these compounds, there are relatively few reports about the initial transformation from oxide to nitride. In this work, the influence of the precursor structure on the active phase formation and catalytic properties of cobalt molybdenum nitrides is examined. Oxidic precursors were obtained by precipitation at different pH values controlled by the addition of aqueous ammonia. The parameters of the precipitation process affected the composition and properties of the materials. The ammonolysis of NH4Co2OH(MoO4)2 ⋅ H2O was investigated in situ with the use of X‐ray powder diffraction and thermogravimetry. The ammonia synthesis activity of the obtained catalysts was compared to the reference iron catalyst. The formation of the Co3Mo intermetallic phase was suggested as the factor governing high activity. [ABSTRACT FROM AUTHOR]

Stimulus-responsive materials containing selenide under oxidizing conditions have wide application prospects, especially in biomedicine. Due to the intricate preparation process, the scarcity of studies on the structure–activity relationship of regulatory factors in the oxidative stimulus response poses challenges to material design. Herein, based on selenol-ene chemistry, a diverse library of unsymmetric selenides is synthesized, enabling systematic investigation into the regulation of selenide oxidative elimination with variable substituent groups and positions. The α/β-positions of β-carbonyl unsymmetric selenides are efficiently modified with electron-donating or electron-withdrawing groups through a one-pot, two-step reaction involving ammonolysis of γ-selenobutyrolactone (SBL), followed by nucleophilic addition with unsaturated acrylate. In situ NMR tracking shows that the oxidative elimination of selenide had a distinct substituent effect. Both the electron and steric effects of the substituent influence the induction period of the selenide oxidative and elimination reactions. With the optimal substituent and position, the selenides would exhibit a timebomb-type response upon oxidation stimulus. Finally, a novel amphiphilic polymer comprising selenide-linked polyethylene glycol (PEG) and cholesterol moieties is synthesized as a representative ROS-sensitive material and exhibits a time-dependent reduction in micelle size. [ABSTRACT FROM AUTHOR]

A sudden increase in polyurethane (PU) production necessitates viable recycling methods for the waste generated. PU is one of the most important plastic materials with a wide range of applications; however, the stability of the urethane linkage is a major issue in chemical recycling. In this work, termination reactions of a model urethane molecule, namely methyl N-phenyl carbamate (MPCate), are investigated using G3MP2B3 composite quantum chemical method. Our main goal was to gain insights into the energetic profile of urethane bond termination and find an applicable chemical recycling method. Hydrogenation, hydrolysis, methanolysis, peroxidation, glycolysis, ammonolysis, reduction with methylamine and termination by dimethyl phosphite were explored in both gas and condensed phases. Out of these chemicals, degradation by H2, H2O2 and CH3NH2 revealed promising results with lower activation barriers and exergonic pathways, especially in water solvation. Implementing these effective PU recycling methods can also have significant economic benefits since the obtained products from the reactions are industrially relevant substances. For example, aniline and dimethyl carbonate could be reusable in polymer technologies serving as potential methods for circular economy. As further potential transformations, several ionizations of MPCate were also examined including electron capture and detachment, protonation/deprotonation and reaction with OH−. Alkaline digestion against the model urethane MPCate was found to be promising due to the relatively low activation energy. In an ideal case, the transformation of the urethane bond could be an enzymatic process; therefore, potential enzymes, such as lipoxygenase, were also considered for the catalysis of peroxidation, and lipases for methanolysis. [ABSTRACT FROM AUTHOR]

The preparation of single-crystalline SrNbO2N particles using the flux method, in which NbOxNy impurities are generated, remains challenging. Herein, Sr5Nb4O15 with a Sr : Nb molar ratio of 1.25 was used as the precursor and NaCl served as flux. The reduction of Nb(V) and formation of NbOxNy impurities during the molten salt assisted thermal ammonolysis process was suppressed by the excess SrO in the precursor. On the other hand, the excess SrO hindered the growth of SrNbO2N grains. The concentration of SrO was controlled by adjusting the precursor-to-flux molar ratio. Meanwhile, the NH3 contact mode of secondary flow or transition flow slowed down the loss of SrO caused by ammonia gas blow-off, and thus controlled the growth of SrNbO2N crystals and defect formation. Well-defined single-crystalline SrNbO2N submicron particles and micron particles were prepared thereby. SrNbO2N particles were assembled into photoanodes by the method of electron-conducting array insertion, and the influence of crystal grain size on the performance of SrNbO2N photoanodes was investigated. [ABSTRACT FROM AUTHOR]

A three‐component phase‐transfer catalytic domino reaction involving cyclohexane‐1,3‐dione‐derived enaminones, 5‐alkenyl rhodanines, and haloalkanes has been developed. This protocol produces a wide range of 3‐thioquinoline‐2,5‐diones in yields of 52–81%. The construction of a C−S bond at the C‐3 position of the quinoline‐2,5‐dione framework expands its structural diversity. Studies into the reaction mechanism revealed that the reaction undergoes a conjugate addition, ammonolysis, elimination, and nucleophilic substitution sequence. The synthetic potential of the reaction was demonstrated by the gram‐scale syntheses of representative products. Chloroalkyl chains were installed on the sulfur atoms of most products obtained in this reaction. Diversified product derivatives were obtained by exploiting the favorable leaving nature of the chloride moiety. [ABSTRACT FROM AUTHOR]

Chemical recycling polymer waste is a highly required technology to follow the current carbon‐neutral trend. Here, we present practical recycling methods for poly (bisphenol A carbonate) (PC) and poly(ϵ‐caprolactone) (PCL). PC can be converted to bisphenol A and urea with excellent product yield at 80 °C via ammonolysis using ammonium salt (ammonium‐formate or ‐carbonate) instead of liquid ammonia that is usually used in previous PC recycling. PCL can be converted to methyl 6‐hydroxy‐hexanoate monomer with excellent yield at 80 °C via methanolysis catalyzed by KOH. [ABSTRACT FROM AUTHOR]

Hydrolysis/alcoholysis/ammonolysis are considered as viable routes for efficient degradation and recycling of polyethylene terephthalate waste plastic. The possible hydrolysis/alcoholysis/ammonolysis pathways for the degradation of ethylene terephthalate dimer were investigated by the density functional theory (DFT) method M06/cc-pVDZ. The geometric structure optimization and frequency calculation of various intermediates, transition states and products involved in the reaction were carried out to obtain thermodynamic and kinetic parameter values. The results show that the reaction energy barrier of the cracking process of ethylene terephthalate dimer can be reduced under the conditions of hydrolysis/alcoholysis/ammonolysis, which makes the reaction easier. Additionally, at 298 K and 1 atm, the total rate constants of hydrolysis/alcoholysis/ammonolysis are 1.51 × 10-43 cm3 molecular-1s−1, 1.86 × 10-41 cm3 molecular-1s−1, and 2.82 × 10-40 cm3 molecular-1s−1, respectively. The hydrolysis products of ethylene terephthalate dimer are mainly terephthalic acid and ethylene glycol; the alcoholysis products of ethylene terephthalate dimer are dimethyl terephthalate and ethylene glycol; and ammonolysis products mainly include terephthalamide and ethylene glycol. Furthermore, this study shows that the Gibbs free energy change of hydrolysis/alcoholysis/ammonolysis is negatively correlated with temperature and an increase in temperature enhance the spontaneity of the reaction.

The reactions of glyoxal (CHO)2) with amines in cloud processes contribute to the formation of brown carbon and oligomer particles in the atmosphere. However, their molecular mechanisms remain unknown. Herein, we investigate the ammonolysis mechanisms of glyoxal with amines at the air‐water nanodroplet interface. We identified three and two distinct pathways for the ammonolysis of glyoxal with dimethylamine and methylamine by using metadynamics simulations at the air‐water nanodroplet interface, respectively. Notably, the stepwise pathways mediated by the water dimer for the reactions of glyoxal with dimethylamine and methylamine display the lowest free energy barriers of 3.6 and 4.9 kcal ⋅ mol−1, respectively. These results showed that the air‐water nanodroplet ammonolysis reactions of glyoxal with dimethylamine and methylamine were more feasible and occurred at faster rates than the corresponding gas phase ammonolysis, the OH+(CHO)2 reaction, and the aqueous phase reaction of glyoxal, leading to the dominant removal of glyoxal. Our results provide new and important insight into the reactions between carbonyl compounds and amines, which are crucial in forming nitrogen‐containing aerosol particles. [ABSTRACT FROM AUTHOR]

Due to the large consumption of polyethylene terephthalate (PET), the accumulated PET wastes have already become an issue to the environment. Research groups focus on the degradation of PET wastes for recycling in the last two decades, and several chemical methods have been investigated including glycolysis, alcoholysis, hydrolysis, aminolysis, and ammonolysis. The studies are faced with the challenges in catalyst development and mechanism insights. Therefore, the achievements are worth reviewing for future exploration and application. This review systematically summarized the catalysts used in PET glycolysis with ethylene glycol (EG), which were categorized into 4 groups including metal oxide, ionic liquid, deep eutectic solvent (DES), and others. The effects of reaction conditions on catalytic performance, reaction mechanism, and kinetics were also analyzed. [ABSTRACT FROM AUTHOR]

A new synthesis of 3′‐deoxy‐3′‐fluoroadenosine for use as an important intermediate of antitumor‐active cyclic dinucleotide is disclosed. The synthesis started with the known 5‐O‐TBDPS‐D‐lyxofuranose 1,2‐acetonides, which was first transformed into a fluorinated compound after the DAST reaction. Desilylation and acidic methanolysis were then finished in one pot. After a sequence of triflation, displacement by OBz as well as benzoylation, perbenzoylated 3‐deoxy‐3‐fluoro‐D‐ribofuranoside was obtained, which would be transformed to 3′‐deoxy‐3′‐fluoroadenosine as the key intermediate of cyclic dinucleotide after ammonolysis. [ABSTRACT FROM AUTHOR]

Titanium nitride (TiN) shows desirable properties for use as an electrocatalyst and catalyst support, as it possesses high electrical conductivity and excellent corrosion resistance. However, the effect of oxygen content in the nitride lattice on its ability to drive the hydrogen evolution reaction (HER) is not well understood. Here, a series of titanium oxynitrides (TiNxO1‐x) with varied nitrogen occupancy (0.53≤x≤1.0) in the bulk have been fabricated by ammonolysis. Their specific activities towards the HER were normalised by the surface areas determined by BET and electrochemical methods. We show that the specific activities of these oxynitrides are strongly correlated with the bulk nitrogen occupancy, despite the similar surface composition derived from XPS analysis. Furthermore, a removal of the oxygen content in the bulk or at the surface was attributed to the upgraded performance (up to 25 % increase) seen during extended chronoamperometry (CA) tests. Our results show that minimising bulk oxygen content in this class of material is critical to achieve a more conductive and active material for the HER. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The N-heterocyclic stannylene [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn] (1) has been synthesised from SnCl2 and the lithium amide [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Li2]. Compound 1 is inert towards H2, CO, CO2, and MeI under ambient conditions. Immediate hydrolysis and ammonolysis was observed with H2O and NH3, respectively. While oxidation reactions of 1 with chalcogens (O2, S8, Se8) afforded only intractable material, the reaction with Ph2Se2 cleanly furnished [Fe{(η5-C5H4)NC6H3-2,6-iPr2}2Sn(SePh)2] (2). Compounds 1 and 2 have been structurally characterised by single-crystal X-ray diffraction. Compound 2 exhibits an intramolecular CH⋯Se contact compatible with a weak hydrogen bond. [ABSTRACT FROM AUTHOR]

Anthraquinone dyes are the second most important type of dyes after azo dyes. In particular, 1-aminoanthraquinone has been extensively utilized in the preparation of diverse anthraquinone dyes. This study employed a continuous-flow method to synthesize 1-aminoanthraquinone safely and efficiently through the ammonolysis of 1-nitroanthraquinone at high temperatures. Various conditions (reaction temperature, residence time, molar ratio of ammonia to 1-nitroanthraquinone (M-ratio), and water content) were investigated to explore the details of the ammonolysis reaction behavior. Operation conditions for the continuous-flow ammonolysis were optimized using Box–Behnken design in the response surface methodology, and ~88% yield of 1-aminoanthraquinone could be achieved with an M-ratio of 4.5 at 213 °C and 4.3 min. The developed process's reliability was evaluated by performing a 4 h process stability test. The kinetic behavior for the preparation of 1-aminoanthraquinone was investigated under continuous-flow mode to guide the reactor design and to gain a deeper understanding of the ammonolysis process. [ABSTRACT FROM AUTHOR]

[Display omitted] 3-[2-(Aminocarbonyl)pyridinium-1-yl]propane-1-sulfonate, a promising medicinal betain, was prepared by a one-pot synthesis with a 89% yield via N -alkylation of ethyl picolinate with 1,3-propanesultone in MeCN followed by ammonolysis. The reaction involving picolinamide in MeOH followed by the treatment with acetone afforded a novel 3,3-dimethyl- 1-oxo-2,3-dihydro-1 H -imidazo[1,5-a]pyridin-4-ium 3-methoxypropane-1-sulfonate. [ABSTRACT FROM AUTHOR]

The variation in crystallinity, morphology and phase of zinc tin hydroxide nanostructures are investigated after annealing at different (oxidizing, non-oxidizing and reducing) atmospheres. The zinc tin hydroxide nanostructures are prepared using hydrolysis assisted co-precipitation method. Annealing in oxidizing (oxygen and air) and non-oxidizing (nitrogen and argon) atmospheres do not have a significant effect on morphological and structural properties. However, the annealing in the reducing (ammonia) atmosphere converts the cubic nanostructures into nanorods and spherical particles. The zinc tin hydroxide forms three new phases (ZnON, SnO 2 and Sn) after annealing in reducing atmosphere. The formation of ZnON and SnO 2 phases are evident in Raman and XPS analysis. The reducing atmosphere (ammonia) changes the reaction kinetics leading to diffusion control crystal growth that could be responsible for such structural and morphological transformation. The bandgap is significantly changed after morphological and structural transformation with notable variation in photocurrent density, charge transfer resistance, and charge carrier concentration. [ABSTRACT FROM AUTHOR]

An interesting ring-closing/ring-opening cascade reaction selectively induced by aliphatic primary amine for the synthesis of functionalized aminomaleimides is described. This work features phenolic hydroxyl as a traceless directing group that forms a critical six-membered intermediate and then a lactone ammonolysis/intramolecular amidation sequence. This two-step, one-pot practical protocol has broad substrate scope (39 examples) and delivers structurally diverse aminomaleimides in good to excellent yields. [ABSTRACT FROM AUTHOR]

In this study, thermal-induced phase separation technology (TIPS) and ammonolysis method were used to prepare modified polylactic acid (PLLA) nanofiber scaffolds with higher hydrophilicity using serine (Ser), glycine (Gly), and lysine (Lys) solutions as ammonolysis agents to prepare modified PLLA nanofibers. The results showed that aminolysis reduced the molecular weight of PLLA, and the introduction of amino acids affected the scaffold morphology and provided a better condition to prepare nanofiber scaffolds. The water contact angle of the modified PLLA nanofiber scaffold prepared by amino acids was improved compared to the unmodified PLLA scaffold. The modified PLLA nanofiber scaffold prepared from Ser, Gly, Lys exhibited lower mechanical properties than the PLLA scaffold prepared from water, meeting the pressure resistance requirements of engineered cartilage tissue scaffolds. Polylactic acid (PLLA) nanofiber scaffolds prepared by thermal-induced phase separation technology and ammonolysis method with serine (Ser), glycine (Gly), or lysine (Lys) solutions as ammonolysis agents. Modification of amino acids leads to a smaller decrease in the melting temperature, while the melting enthalpy and crystallinity increased numerically. It is conducive to promote the formation of nanofibers. [ABSTRACT FROM AUTHOR]

[Display omitted] • A mild and efficient synthesis of 3-aza-obeticholic acid starting from obeticholic acid (OCA). • Regiomeric amino-alcohols were prepared from a mixture of Baeyer-Villiger-reaction-derived lactones by ammonolysis and Hofmann degradation. • Annulation of N -Boc-protected amino-alcohols was accomplished via mesylation or a Dess-Martin oxidation/hydrogenation sequence. • Our synthesis is scalable and can be employed to access other 3-aza-bile acids. Bile acids (BAs) are steroidal molecules that play important roles in nutrient absorption, distribution, and excretion. They also act on specific receptors implicated in various metabolic and inflammatory diseases demonstrating their importance as potential drug candidates. Accordingly, there has been a concerted effort to develop new BA derivatives to probe structure–activity relationships with the goal of discovering BA analogues with enhanced pharmacological properties. Among the many steroidal derivatisations reported, the formation of endocyclic azasteroids appeals due to their potential to deliver altered biological responses with minimal change to the steroidal superstructure. Here, we report the synthesis of 3-aza-obeticholic acid (6) via a regioconvergent route. Ammoniolysis of lactones, formed from an m -CPBA-mediated Baeyer-Villiger reaction on a 3-keto-OCA derivative, furnished protected intermediate amido-alcohols which were separately elaborated to amino-alcohols via Hofmann degradation with BAIB. Upon individual N -Boc-protection, these underwent annulation to the 3-aza-A-ring when subjected to either mesylation or a Dess-Martin oxidation/hydrogenation sequence. Global deprotection of the 3-aza-intermediate delivered 3-aza-OCA in ten steps and an overall yield of up to 19%. [ABSTRACT FROM AUTHOR]

A new ammonolysis technology is developed for producing targeted functional C4 acids from a renewable feedstock, i.e., poly(3-hydroxybutyrate) (PHB). β-Aminobutyric acid (BABA) and β-hydroxybutyric acid (BHBA) are produced from PHB with an aggregate selectivity of 99% under a one-pot catalyst-free reaction at 140 °C. The product distribution can be controlled by ammonia concentration, and the reaction mechanism is investigated based on quantum chemical calculation. This work establishes a promising route for the production of β-substituted C4 acids via a green and sustainable pathway. [ABSTRACT FROM AUTHOR]

In this study, thermal-induced phase separation technology (TIPS) and ammonolysis method were used to prepare modified polylactic acid (PLLA) nanofiber scaffolds with higher hydrophilicity using serine (Ser), glycine (Gly), and lysine (Lys) solutions as ammonolysis agents to prepare modified PLLA nanofibers. The results showed that aminolysis reduced the molecular weight of PLLA, and the introduction of amino acids affected the scaffold morphology and provided a better condition to prepare nanofiber scaffolds. The water contact angle of the modified PLLA nanofiber scaffold prepared by amino acids was improved compared to the unmodified PLLA scaffold. The modified PLLA nanofiber scaffold prepared from Ser, Gly, Lys exhibited lower mechanical properties than the PLLA scaffold prepared from water, meeting the pressure resistance requirements of engineered cartilage tissue scaffolds.Polylactic acid (PLLA) nanofiber scaffolds prepared by thermal-induced phase separation technology and ammonolysis method with serine (Ser), glycine (Gly), or lysine (Lys) solutions as ammonolysis agents. Modification of amino acids leads to a smaller decrease in the melting temperature, while the melting enthalpy and crystallinity increased numerically. It is conducive to promote the formation of nanofibers. [ABSTRACT FROM AUTHOR]

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The direct synthesis of β-NH2 alcohols via flexible ammonolysis of epoxides is still a challenging and unresolved problem. Herein, we present a strategy of "trading space for time under weakly activated catalysis" and "shielding the reactivity of the product", and thereby developed a novel single-step ammonolysis reaction of epoxides with ammonia. A stoichiometric amount of HCO2NH4 as an additive plays a dual role in the global activation of substrates and in completely suppressing the side reaction of excessive alkylation. A broad scope of substrates including terpene- and steroid-derived epoxides cleanly afforded the target β-NH2 alcohols in good to excellent yields under easily adjustable mild conditions. Furthermore, this synthetic protocol is metal-free and eco-friendly and could be used for the gram-scale synthesis of biologically active β-NH2 alcohols that could be converted to diverse functionalized molecules with ease. [ABSTRACT FROM AUTHOR]

This paper describes a safer, scalable and continuous process for synthesis of picramide. The process consists of two steps: step‐1. nitration of p‐nitroanisole (PNAN) to 2,4,6‐trinitrianisole (TNAN); step‐2. ammonolysis of TNAN to picramide. Both the steps were optimized in flow, with yield of 90% and 98% in step‐1 and step‐2 respectively. Picramide with HPLC purity greater than 99% was obtained. When compared with batch, in step‐1, flow process provided significant advantage in selectivity and yield. The optimized flow process was scaled to 25 g/hr production rate in a laboratory flow reactor. The method can be considered fit for the safe production of picramide at commercial scale. [ABSTRACT FROM AUTHOR]

A synthetic route to BIX-01294 was designed by means of retrosynthetic analysis and convergent synthesis. Using 2-amino-4,5-dimethoxybenzoic acid and urea as the starting materials, BIX-01294 was synthesized in the four following steps: cyclization, chlorination and two steps of ammonolysis. In contrast to the previously described approaches to BIX-01294, our final step conditions do not require microwave irradiation, utilize cheap and simple methanesulfonic acid as a catalyst to promote the synthesis of the target BIX-01294 under mild conditions (PrnOH, reflux, 5 h) in 75.5% yield. The overall yield of BIX-01294 over four steps was 26.4%. [ABSTRACT FROM AUTHOR]

Wide band gap semiconductor niobate photocatalysts with Dion-Jacobson layered perovskite structure were nitrogen-doped via simple gas–solid reaction to extend their absorption into the visible light range. Nitrogen doping was performed using ammonia as precursor, resulting in decreased band gaps of doped AB2Nb3O10 compounds (A = Cs, Rb, K; B = Ca, Sr) down to 2.5 eV. The resulting materials were investigated concerning their chemical and electronic structures. Nitrogen-doped AB2Nb3O10 crystals showed a clear red shift in absorption. Photocatalytic performance tests for the doped materials evaluated the capability of H2 production under simulated solar irradiation. The addition of carbonates to the gas–solid reaction turned out to be advantageous for the reduction of defects and the preservation of photocatalytic activity of nitrogen-doped layered niobates AB2Nb3O10. [ABSTRACT FROM AUTHOR]

While a few derivatives of cinnamamides exhibited anti-inflammatory and/ or analgesic activity, in this study, we developed a highly efficient method for the synthesis of cinnamamides from methyl cinnamates and phenylethylamines catalyzed by Lipozyme® TL IM in continuous-flow microreactors. The reaction parameters and broad substrate range of the new method was studied. Maximum conversion (91.3%) was obtained under the optimal condition of substrate molar ratio of 1:2 (methyl 4-chlorocinnamate: phenylethylamine) at 45 ° C for about 40 min. The remarkable features of this work include short residence time, mild reaction conditions, easy control of the reaction process, and that the catalyst can be recycled or reused, which provide a rapid and economical strategy for the synthesis and design of cinnamamide derivatives for further research on drug activity. [ABSTRACT FROM AUTHOR]

In order to make recycling a viable strategy for post-consumer plastics, economically feasible revalorization processes must be developed. The ammonolysis of polyamides can be such a cutting-edge recycling technology; however, due to the rigid structure of these polyamide plastics, operating conditions of current ammonolysis processes are harsh, including high temperatures (>300 °C) and high NH3 pressures. Here, we report a very green and elegant ammonolysis process of the widely abundant polyamide 66 by using a hard Lewis acid catalyst and 1 bar of NH3 in a simple glycol solvent at 200 °C. Computational studies revealed that especially the vicinal diol moiety of these glycol solvents plays a key role in activation of the ammonia nucleophile, with glycerol being the most effective solvent, reaching the depolymerization equilibrium after 20 h even without a catalyst. To our delight, a biosourced glycerol (obtained from the saponification of triglycerides) could also directly serve as a suitable solvent, even outperforming the ammonolysis process in highly purified glycerol. [ABSTRACT FROM AUTHOR]

Robust super-hydrophobic ceramic membranes consisting of layered structure Si 2 N 2 O grains and organosilane-derived inorganic nanoparticles were successfully fabricated and employed for membrane distillation. First, phase inversion and sintering method were used to prepare porous Si 2 N 2 O membranes. The slurry composition and sintering temperature were optimized to obtain a pure phase Si 2 N 2 O membrane with high bending strength, tailored average pore size, and high permeability. Then, the Si 2 N 2 O membranes were modified with organosilane-derived inorganic nanoparticles through ammonolysis and pyrolysis reactions. Due to the micro and nano-hierarchical rough structures and the presence of -Si-CH 3 groups, the membranes showed super-hydrophobicity with a water contact angle of 152 ± 1°. Finally, the membranes were applied to desalinate seawater by sweeping gas membrane distillation. A stable water flux of 76 ± 0.9 L/(m2 day) with a salt rejection of > 99% was recorded during 30 h distillation test at 75 °C, demonstrating the stability and durability of the membranes. [Display omitted] • Layered structure Si 2 N 2 O membrane with naturally rough grains was fabricated. • Super-hydrophobicity was obtained after modifying by the inorganic nanoparticles. • The super-hydrophobic membrane has micro and nano-hierarchical rough structures. • The membrane was successfully employed in membrane distillation process. [ABSTRACT FROM AUTHOR]

The effective synthesis of benzoconduritols C and D is reported. Oxidation of oxabenzonorbornadiene followed by acetylation with Ac2O/pyridine or AcCl/CH2Cl2 gave the corresponding exo-diacetate compound stereoselectively. Acid-catalyzed ring opening of the bridged ether bond (the 1,4-anhydo bond) with Ac2O in the oxabenzonorbornadiene system to produce benzoconduritol tetraacetates followed by ammonolysis furnished the desired benzoconduritols C and D, respectively. The novel benzoconduritols (9, 10, 15, 16, and 17) were evaluated for the first time in terms of their potential antioxidant, anti-inflammatory, and enzyme inhibition activities. Most of the complexes exhibited moderate activity. Especially 15 (IC50 = 0.374 mM) and 10 (IC50 = 0.450 mM) have better anti-inflammatory effect when compared to ibuprofen (IC50 = 0.437 mM). Furthermore, the benzoconduritol C 9 has better α-glucosidase inhibition potential with the IC50 value of 0.437 mM than acarbose (IC50 = 0.445 mM). The results of this study point out that most of these molecules have the potential to provide an alternative for the clinical control of inflammation and diabetes due to their anti-inflammatory and anti-glucosidase activities. [ABSTRACT FROM AUTHOR]

Cellulose‐based paper samples were surface‐modified by a polymeric single‐source precursor prepared from perhydropolysilazane (PHPS) and iron(III)acetylacetonate (Fe(acac)3) and ammonolyzed at 500°C, 700°C, 900°C, and 1000°C, leading to C/SiFe(N,C)O‐based ceramic papers with in situ‐generated hierarchical micro/nano‐morphology. As reference, cellulose‐free samples were prepared under the same conditions. Upon thermal treatment, the microstructure evolutions of the resulting ceramic paper and the reference sample were comparatively investigated. Scanning electron microscopy (SEM) showed that for all temperatures, the ceramic papers exhibit the same morphology as the template, however, with noticeable shrinkage and curling, particularly evident at higher temperatures. X‐ray diffraction (XRD) measurements of the reference samples and the ceramic papers showed a similar crystallization behavior and phase evolution in both materials. In the ceramic paper, the crystallization process seems to occur at a later time. The results provide a comprehensive understanding of the investigated C/SiFe(N,C)O‐based ceramic system. It was shown that use of the cellulose‐based paper template has the benefit of retaining the microstructure and furthermore, apart from transforming the cellulose fibers into turbostratic carbon, does not change the phase evolution during the polymer‐to‐ceramic transformation, allowing at the same time the manufacturing of novel morphologically complex parts by a convenient one‐pot synthesis approach. [ABSTRACT FROM AUTHOR]

By employing the highly reducing aluminyl complex [K{(NON)Al}]2 (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene), we demonstrate the controlled formation of P42− and P44− complexes from white phosphorus, and chemically reversible inter‐conversion between them. The tetra‐anion features a unique planar π‐bonded structure, with the incorporation of the K+ cations implicit in the use of the anionic nucleophile offering additional stabilization of the unsaturated isomer of the P44−fragment. This complex is extremely reactive, acting as a source of P3−: exposure to ammonia leads to the release of phosphine (PH3) under mild conditions (room temperature and pressure), which contrast with those necessitated for the direct combination of P4 and NH3 (>5 kbar and >250 °C). [ABSTRACT FROM AUTHOR]

By employing the highly reducing aluminyl complex [K{(NON)Al}]2 (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene), we demonstrate the controlled formation of P42− and P44− complexes from white phosphorus, and chemically reversible inter‐conversion between them. The tetra‐anion features a unique planar π‐bonded structure, with the incorporation of the K+ cations implicit in the use of the anionic nucleophile offering additional stabilization of the unsaturated isomer of the P44−fragment. This complex is extremely reactive, acting as a source of P3−: exposure to ammonia leads to the release of phosphine (PH3) under mild conditions (room temperature and pressure), which contrast with those necessitated for the direct combination of P4 and NH3 (>5 kbar and >250 °C). [ABSTRACT FROM AUTHOR]

By employing the highly reducing aluminyl complex [K{(NON)Al}]2 (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene), we demonstrate the controlled formation of P42− and P44− complexes from white phosphorus, and chemically reversible inter‐conversion between them. The tetra‐anion features a unique planar π‐bonded structure, with the incorporation of the K+ cations implicit in the use of the anionic nucleophile offering additional stabilization of the unsaturated isomer of the P44−fragment. This complex is extremely reactive, acting as a source of P3−: exposure to ammonia leads to the release of phosphine (PH3) under mild conditions (room temperature and pressure), which contrast with those necessitated for the direct combination of P4 and NH3 (>5 kbar and >250 °C). [ABSTRACT FROM AUTHOR]

By employing the highly reducing aluminyl complex [K{(NON)Al}]2 (NON=4,5‐bis(2,6‐diisopropylanilido)‐2,7‐di‐tert‐butyl‐9,9‐dimethylxanthene), we demonstrate the controlled formation of P42− and P44− complexes from white phosphorus, and chemically reversible inter‐conversion between them. The tetra‐anion features a unique planar π‐bonded structure, with the incorporation of the K+ cations implicit in the use of the anionic nucleophile offering additional stabilization of the unsaturated isomer of the P44−fragment. This complex is extremely reactive, acting as a source of P3−: exposure to ammonia leads to the release of phosphine (PH3) under mild conditions (room temperature and pressure), which contrast with those necessitated for the direct combination of P4 and NH3 (>5 kbar and >250 °C). [ABSTRACT FROM AUTHOR]

A detailed mechanism investigation of the formation of B−N, Si−N and C−N bonds is conducive to the design and synthesis of siliconboroncarbonitride (SiBCN) ceramics to meet application requirements under extreme conditions. Boron trichloride (BCl3), methyldichlorosilane (MDCS) and methylvinyldichlorosilane (MVCS) are the most commonly used raw materials, and they can react with amino compounds, such as ammonia (NH3), methyl ammonium (CH3NH2), and hexamethyldisilazane (HMDZ, (CH3)6Si2NH) in the synthesis of SiBCN precursors. In this paper, quantum chemical calculations were used to study the ammonolysis mechanism of three raw materials with three amino compounds at the M06‐2X/6‐311G(d,p) level of theory. The structural properties, reaction pathways, energy barriers, reaction rates, and other aspects were discussed in detail. The results show that compounds containing B−N, Si−N and C−N bonds can be formed through a synergistic reaction mechanism with the release of ammonium chloride or trimethylchlorosilane (TMCS). The ammonolysis processes of BCl3 have absolute advantages in both kinetics and thermodynamics. The reaction of MDCS has the lowest energy barrier. All ammonolysis reactions are thermodynamically exothermic processes. The calculated results agree well with the experimental observations and provide an explanation for the initiation process of precursor synthesis. [ABSTRACT FROM AUTHOR]

The tandem Knoevenagel—Michael—intramolecular ammonolysis—alkylation reaction was used to synthesize functionalized tetrahydropyridones. The molecular and crystal structures of four pyridone derivatives were studied by X-ray diffraction. [ABSTRACT FROM AUTHOR]