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Wittig reaction between substituted phosphonium salts and (hetero)aromatic and alkyl carbonyl compounds in Deep Eutectic Solvents has been developed under a scalable and friendly protocol. Highly efficient reactions were successfully run with a wide range of bases including organic (DBU, LiTMP, t‐BuOK) and inorganic (NaOH, K2CO3) ones in ChCl/Gly 1 : 2 (mol/mol) as solvent under mild conditions, at room temperature and under air. The proposed protocol was applied to a wide range of substrates, including (hetero)aromatic aldehydes with substituents as halogens (I, Br, Cl), EDG (alkoxy, methyl), EWG (NO2, CF3) or reactive groups as CN, esters, and ketones. Vinylic, alkynyl and cycloalkyl, alicyclic and α,β‐unsaturated aldehydes can also be used. Highly electrophilic ketones gave good yields. The diastereoselectivity of the reaction is in complete agreement with the E/Z ratio predictable under traditional conditions. We demonstrated that the protocol is scalable to 2 g (5 mmol) of phosphonium salt, furthermore the proposed workup protocol allows to remove TPPO without need of additional chromatographic purification. [ABSTRACT FROM AUTHOR]

The various steps in the mechanism of olefin polymerizations mediated by neutral rare‐earth metallocene complexes are discussed. The complexes are either trivalent hydride and alkyl rare‐earth compounds or divalent metallocenes that are activated by the monomer via an oxidation step. The stereospecific polymerizations of conjugated dienes based on the association of a cationic metallocene complex and an alkylaluminum and the polymerization mechanism based on monomer insertion into an aluminum‐carbon bond are also discussed. The exploitation of metallocene complexes for the copolymerization of olefins with conjugated dienes is the subject of a third part of this review. The synthesis of new elastomers called ethylene butadiene rubber (EBR) is highlighted. Finally, the use of rare‐earth metallocenes in macromolecular engineering is detailed. This includes the synthesis of functional polyolefins and block copolymers including thermoplastic elastomers. [ABSTRACT FROM AUTHOR]

The addition of biogas liquid is a practical way to improve the yield of biological coalbed methane. The microbial composition in biogas liquid is complex, and whether it could participate in the sulfur conversion of coal remains unknown. In this study, sulfur conversion-related microbial communities were enriched from biogas liquid, which was dominated by genera Anaerosolibacter, Bacillus, Hydrogenispora, and Oxobacter. The co-culture of these groups with coal significantly changed the coal microbial community composition but did not increase the content of CH4 and H2S. The changed microbial communities mainly belonged to phyla Firmicutes, Proteobacteria, and Actinobacteriota, and increased the relative abundance of genera Bacillus, Thermicanus, Hydrogenispora, Oxobacter, Lutispora, Anaerovorax, Desulfurispora, Ruminiclostridium, and Fonticella. From the microscopic structure of coal, an increase in the number of holes and roughness on the surface of the coal was found but the change of surface functional groups was weak. In addition, the addition of S-related microbial communities increased the contents of phoxim, methylthiobenzoylglycine and glibornuride M5 in aromatic compounds, as well as the content of lauryl hydrogen sulfate in alkyl compounds. Furthermore, the dibenzothiophene degradation-related microbial communities included Bacillus, Brevibacillus, Brevundimonas, Burkholderia-Caballeronia-Paraburkholderia, and Thermicanus, which can break C-S bonds or disrupt benzene rings to degrade dibenzothiophene. In conclusion, the S-related microbial communities in biogas liquid could rebuild the coal microbial community and be involved in the conversion process of organic sulfur in coal. [ABSTRACT FROM AUTHOR]

[Display omitted] A series of heterogeneous catalysts, designated as POP- n -Pd (where n = 1, 2, 3, or 4), were synthesized by polymerizing a six-membered N -heterocyclic compound with an alkyl substituted group monomer (S1), using divinylbenzene (DVB) as crosslinkers. This process was followed by the incorporation of palladium (Pd) nanoparticles. The impact of the substituted group and the S1 :DVB ratio in the catalysts, together with the reaction conditions, was investigated to assess their influence on the catalytic performance in converting propylamine, carbon dioxide (CO 2) and 4-iodoanisole to oxazolidinones. The POP-1-Pd catalyst, featuring a methyl substituted group and a S1 :DVB ratio of 1:4, exhibited remarkable efficiency, resulting in an excellent yield of 96 % under room temperature and ambient pressure conditions. Furthermore, it has demonstrated wide applicability across a variety of substrates and in the treatment of lime kiln exhaust gas. Additionally, POP-1-Pd can be used in a gram-scale reaction and maintains its performance after six recycles, with no significant decline in yield. The possible catalytic mechanism is proposed as follows: the catalyst's pores adsorb both CO 2 and substrates, creating a high concentration reactant enrichment microenvironment. This facilitates the activation of both CO 2 and substrates by the imidazole moiety and Pd nanoparticles in the catalyst, thereby generating oxazolidinones. [ABSTRACT FROM AUTHOR]

Dedicated coating materials for anechoism and furtivity in underwater acoustics must exhibit a strong reliability regarding their mechanical resistance to hydrostatic pressure. Soft porous materials, especially, a distribution of soft porous beads within a polyurethane matrix, have been previously proposed as an acoustic insulator device. The purpose of the present letter is to investigate the attenuation efficiency of soft porous silicone beads-based materials while being exposed to uniaxial loads mimicking hydrostatic pressures encountered in underwater acoustics. The acoustic performance of this locally resonant material is then compared to the classical coating technology using micro-balloons. The use of an adapted surfactant (a silicone alkyl polyether compound) in the fabrication process of the soft porous silicone-based beads, obtained through an emulsion templating process, leads to particles exhibiting an open porosity. The (resonant) attenuation of the soft porous beads-based material remains greater than the micro-balloons-based material until several bars. Above this critical resilience value, the mechanical stress irreversibly damages the soft porous beads. [ABSTRACT FROM AUTHOR]

ABSTRACT By using a multicomponent reaction involving isatins, diamines or aminoalcohols, activated acetylenic compounds, haloketones, and ammonium acetate in aqueous media in the presence of Cu@Fe3O4/SiO2@MWCNTs as new catalyst, the novel pyridopyrroloindole was produced in high yields. This catalyst was produced by employing Petasites hybridus rhizome water extract as a green media and moderate base. The pyridopyrroloindole derivatives were newly synthesized compounds, and their antioxidant properties were assessed using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical trapping and ferric reducing ability of plasma (FRAP) experiments. The pyridopyrroloindole 6b showed higher performance than butylated hydroxytoluene (BHT) and tert‐butylhydroquinone (TBHQ) better results. This method is used to make pyridopyrroloindole derivatives, and it has the advantages of a quick reaction, high yields, and the ability to separate the products easily. [ABSTRACT FROM AUTHOR]

Monoanionic gold bis(dithiolene) complexes were recently shown to display activity against ovarian cancer cells, Gram-positive bacteria, Candida strains and the rodent malaria parasite, P. berghei. To date, only monoanionic gold(III) bis(dithiolene) complexes with a thiazoline backbone substituted with small alkyl chains have been evaluated for biomedical applications. We now analyzed the influence of the length and the hydrophobicity vs. hydrophilicity of these complexes' alkyl chain on their anticancer and antiplasmodial properties. Isomer analogues of these monoanionic gold(III) bis(dithiolene) complexes, this time with a thiazole backbone, were also investigated in order to assess the influence of the nature of the heterocyclic ligand on their overall chemical and biological properties. In this report we present the total synthesis of four novel monoanionic gold(III) bis(dithiolene) complexes with a long alkyl chain and a polyoxygenated (PEG) chain aiming to improve their solubility and biological properties. Our results showed that the complexes with a PEG chain showed promising anticancer and antiplasmodial activities beside improved solubility, a key parameter in drug discovery and development. [ABSTRACT FROM AUTHOR]

Molecular structure-editing through nitrogen insertion offers more efficient and ingenious pathways for the synthesis of nitrogen-containing compounds, which could benefit the development of synthetic chemistry, pharmaceutical research, and materials science. Substituted amines, especially nitrogen-containing alkyl heterocyclic compounds, are widely found in nature products and drugs. Generally, accessing these compounds requires multiple steps, which could result in low efficiency. In this work, a molecular editing strategy is used to realize the synthesis of nitrogen-containing compounds using aryl alkanes as starting materials. Using derivatives of O-tosylhydroxylamine as the nitrogen source, this method enables precise nitrogen insertion into the Csp2-Csp3 bond of aryl alkanes. Notably, further synthetic applications demonstrate that this method could be used to prepare bioactive molecules with good efficiency and modify the molecular skeleton of drugs. Furthermore, a plausible reaction mechanism involving the transformation of carbocation and imine intermediates has been proposed based on the results of control experiments. Substituted amines, especially nitrogen containing alkyl heterocyclic compounds, are widely found in nature products and drugs, but generally accessing these compounds requires multiple steps. Herein, the authors report a molecular editing strategy for the synthesis of nitrogen-containing compounds using aryl alkanes as starting materials. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT) is a minimally invasive treatment that shows promise in replacing traditional surgery, chemotherapy, and radiotherapy. In this study, 15 NO-type porphyrin ferulic acid derivatives were synthesized using acyl chlorination, substitution, and complexation with metal salts. After 10 s of light irradiation, the NO-type porphyrin–ferulic acid derivatives could effectively quench DPBF, among which compounds 6a–6e and compounds 7a–7e reduce the fluorescence intensity of DPBF to below 30, indicating that they have a good ability to produce singlet oxygen. Additionally, NO-type porphyrin–ferulic acid derivatives rapidly released NO in 5 min and substantially increased its level within 60 min. The anti-tumour activity experiments showed that NO porphyrin ferulic acid derivatives could produce different degrees of phototoxicity toward A549 cells and HepG2 cells under light conditions. The compounds with shorter alkyl chains showed better antitumor activity, while the elongation of alkyl chains reduced the activity of the compounds. Among these compounds, compound 7a showed optimal inhibition (IC50 = 43.82 ± 2.50) and had the potential to be a combination therapeutic agent for photodynamic therapy and chemotherapy. [ABSTRACT FROM AUTHOR]

Aliphatic quaternary ammonium salts (QASs) with intrinsic photoluminescence (PL) have drawn increasing attention due to the importance of exploring the mechanism of ionic emissive clusters, whereas it remains challenging to clarify structure–property relationships. Here, the effective modulation of photophysical properties of gemini aliphatic QASs (n‐BTADB) is managed by altering the alkyl chain length. Boosted quantum yields (up to 24.6%), prolonged phosphorescence lifetimes (up to 515.2 ms), and varied PL colors are achieved by manipulating the aggregation states of the compounds. Interlaced herringbone packing patterns and strong ionic interactions facilitate the intersystem crossing process and stabilize the triplets. The confluence of varied hydrophobic interactions and chain flexibility results in the fluctuation of phosphorescence lifetimes as the alkyl chain lengthens. Furthermore, the single‐component white‐light emission is obtained in 12‐HBTADB crystals by introducing electron‐rich hydroxyls. These results shed new light on the structure–property relationships of ionic emissive clusters and the rational design of nonconventional ionic luminophores. [ABSTRACT FROM AUTHOR]

Inflammation is a response to injury and infection in an organism. It can be categorized as acute or chronic. Chronic inflammation is the underlying cause of many diseases such as Alzheimer disease, diabetes, rheumatoid arthritis, atherosclerosis, and cardiovascular diseases. Recent studies have proven the antiinflammatory properties of 1,4-dihydropyridines (1,4-DHPs) and their derivatives, which have many biological activities including the blocking of calcium channels. In this study, 15 compounds that are condensed derivatives of 1,4-DHPs, with the general structure of hexahydroquinoline-3-carboxylate, were synthesized. These compounds, expected to show inhibitory activity against inflammatory mediators, were obtained by the reaction of 4-(difluoromethoxy)benzaldehyde, substituted/ nonsubstituted 1,3-cyclohexanedione derivatives, and appropriate alkyl acetoacetate compounds in the presence of ammonium acetate as a nitrogen source according to the Hantzsch synthesis method. The structures of the synthesized compounds were elucidated by IR, ¹H NMR, 13C NMR, and HRMS methods. The cytotoxic properties of the compounds were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method in the 3T3 cell line. Among the 15 compounds, the three compounds with the lowest levels of cytotoxic effects were selected for further experiments. Inflammation was induced by lipoxygenase and the effects of the selected compounds on the levels of reactive oxygen species, cytokines, and complement C3 and C9 regulatory proteins were investigated. It was found that the three selected compounds decreased the levels of transforming growth factor-beta 1 (TGF-β1). Among these compounds, compound 3e provided the most significant decrease in this cytokine. Moreover, 3e increased both C3 and C9 levels. Molecular modeling studies also showed that 3e had better affinity for TGF-β1. When the binding modes of these compounds in the active site of TGF-β1 were analyzed, it was found that compound 3e had hydrophobic interactions with amino acids Leu142, Tyr84, and Ile13; halogen bond interactions with Asp92; and hydrogen bond interactions with Ser89, Gly88, and Gly14 in the active binding site. Further in vitro and in vivo studies are needed to show the possible mechanism of action of compound 3e. [ABSTRACT FROM AUTHOR]

This study conducted in situ combustion oxidation experiments on crude oil from Block D within the Liaohe Oilfield, utilizing a kettle furnace low-pressure oxidation reaction method at various temperatures. The molecular composition of oxidation products was analyzed using gas chromatography–mass spectrometry (GC–MS) and high-resolution mass spectrometry. The results reveal that the molecular composition of the products remains relatively stable up to 300 °C, exhibiting a slight increase in C13-C30 alkanes. The ratio of the peak area for C21 to bisnorhopane is 0.082. From 300 °C to 450 °C, compounds with long alkyl chains gradually undergo thermal cracking, resulting in a significant increase in the production of alkanes within the C10–C30 range. The concentration of saturated hydrocarbons produced through thermal cracking reaches its maximum at a temperature of 400 °C. The most abundant peak of n-alkane is observed at C21, with a quantified ratio of peak area for C21 to bisnorhopane at 6.5, indicating a two-order magnitude increase compared to crude oil. From 500 °C to 600 °C, compounds undergo more profound thermal cracking and condensation processes. The predominant hydrocarbons consist of aromatic molecules containing two to six rings substituted with short side chains. The double bond equivalent (DBE) values of carbazoles and carboxylic acids are determined as 30 and 25, respectively. At 600 °C, the peak area ratio of naphthalene to biodecane is 300, indicating a remarkable increase of five orders of magnitude compared to the crude oil. The present study elucidates the correlation between the characteristics of combustion components in crude oil and the corresponding combustion temperature. Primary cracking reactions within crude oil are promoted effectively when keeping the combustion zone at 350 °C and 450 °C. This process significantly reduces the viscosity of heavy oil and enhances its fluidity. [ABSTRACT FROM AUTHOR]

Newly synthesized gemini quaternary ammonium salts (QAS) with different counterions (bromide, hydrogen chloride, methylcarbonate, acetate, lactate), chain lengths (C12, C14, C16) and methylene linker (3xCH2) were tested. Dihydrochlorides and dibromides with 12 carbon atoms in hydrophobic chains were characterized by the highest biological activity against planktonic forms of yeast and yeast-like fungi. The tested gemini surfactants also inhibited the production of filaments by C. albicans. Moreover, they reduced the adhesion of C. albicans cells to the surfaces of stainless steel, silicone and glass, and slightly to polystyrene. In particular, the gemini compounds with 16-carbon alkyl chains were most effective against biofilms. It was also found that the tested surfactants were not cytotoxic to yeast cells. Moreover, dimethylcarbonate (2xC12MeCO3G3) did not cause hemolysis of sheep erythrocytes. Dihydrochlorides, dilactate and diacetate showed no mutagenic potential. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Key Scientists The construction of acyclic quaternary carbon stereocenters, which are ubiquitous in many bioactive compounds, pharmaceuticals and natural products, has been a long persuit in synthetic organic chemistry. Among numerous methods, enantioselective nickel‐catalysis has attracted incremental attention in recent years. This review summarizes the recent development in the asymmetric strategies, research progress, mechanistic investigations for the generation of acyclic quaternary carbon stereocenters via enantioselective nickel catalysis.In 2006, the Zhou group and RajanBabu group realized the nickel‐catalyzed enantioselective hydrovinylation of α‐substituted styrenes and ethylene to construct acyclic quaternary carbon stereocenters (QCSs) by using spiro‐ and binaphthyl phosphoramidite ligands, respectively. In 2016, Watson developed a nickel‐catalyzed Suzuki‐Miyaura arylation to generate acyclic QCSs via chirality transfer reaction. In 2017, the Feng and the Fu group developed nickel‐catalyzed enantioselective conjugated/Michael additions to build acyclic QCSs, respectively. In 2020, the Fang group made the first success in the construction of QCSs by nickel‐catalyzed hydrocyanation of alkenes and allenes. In 2021, Gregory C. Fu and co‐workers disclosed a nickel‐catalyzed enantioselective α‐functionalization of carbonyl compounds that could form acyclic QCSs. At the same time, the Shi group constructed chiral acyclic QCSs via nickel‐catalyzed functionalization of alkenes. In 2023, Kleij and co‐workers applied a new strategy for Ni‐catalyzed regio‐ and enantioselective homoallylic coupling to construct acyclic QCSs. In the same year, Tao and co‐workers demonstrated a novel strategy that is dinickel‐catalyzed enantioselective α‐alkylation of carbonyl compounds with alkyl iodides. [ABSTRACT FROM AUTHOR]

In this work, we synthesized a series of nine tetraalkylammonium salts derived from N‐methyl morpholine and assessed their antibacterial efficacy against Methicillin‐Resistant Staphylococcus aureus (MRSA). The investigated morpholinium cations differ by the length of one linear alkyl chain, which ranges from 1 to 18 carbon atoms. We found that compounds with alkyl chains in the n‐C12H25‐(n‐dodecyl) to C16H33‐(n‐hexadecyl) display the highest bactericidal effects, exhibiting Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) values of 3.9 μg/mL – surpassing the effectiveness of the commercial drug Linezolid. Conversely, compounds with shorter chains (<5 carbon atoms) are inactive against MRSA, establishing a clear structure‐activity relationship. Assays on A. salina reveal that short‐alkyl‐chain morpholinium derivatives, inactive against MRSA), are moderately toxic, while the strongest bactericides of our set demonstrate high or extreme toxicity to A. salina. Our findings underscore the potential of morpholine derivatives as a means to control Methicillin‐Resistant Staphylococcus aureus and pinpoint the need to develop safe applications for these compounds given their potential toxicity. [ABSTRACT FROM AUTHOR]

Rare‐earth‐metal (Ln) alkyl and aryl compounds feature highly reactive, thermally labile [Ln−C] σ‐bonds which result in rapid and violent decomposition in the presence of air and moisture. Nevertheless, such [Ln−C] moieties display important intermediate species in numerous organic transformations. Reagents containing [Ln−C] bonds are deliberately generated in situ like Imamoto‐type reagents Ln(III)Cl3/RLi (routinely at low temperatures) or "heavy" lanthanide‐Grignard compounds RLnX. Samarium(III)‐alkyl species are supposed intermediates of SmI2‐promoted Barbier‐type carbon–carbon coupling reactions. Alkyl/aryl ligand exchange at Ln(III) centers has been identified as the crucial step of lanthanide–halogen‐exchange reactions. In the meantime, several such mixed alkyl/halogenido complexes, devoid of an ancillary ligand, could be isolated and scrutinized with regard to structure and reactivity. More recently, Ln(III)‐alkylidene complexes could be accessed, structurally authenticated and successfully employed in Tebbe‐like olefination reactions of ketones. [ABSTRACT FROM AUTHOR]

α-Chiral alkyl phosphines are privileged structural motifs with a wide application in organic and medical synthesis. It is highly desirable to develop stereoselective methods to prepare these enantioenriched molecules. The incorporation of C(sp³)-H functionalization and chiral phosphine chemistry is much less explored, probably because of the weak reactivity of C(sp³)-H bonds and/or the challenging site-and stereoselectivity issues. Herein, we disclose a synergistic catalysis system to enable an enantioselective radical addition process of α-substituted vinylphosphine oxides. An array of diverse α-chiral alkyl phosphors compounds is smoothly accessed by using the readily available chemicals as the inert C(sp³)-H bond reagent, such as sulfides, amines, alkenes, and toluene derivatives, exerting remarkable chemo-, site-, and enantioselectivity. On the basis of the mechanistic studies, both the C(sp³)-H bond activation and the stereochemistry-determining step are proposed to involve a single-electron transfer/proton transfer process. [ABSTRACT FROM AUTHOR]

In this work, we conducted a comparative analysis of the metal ion sensing capabilities of two pyridine‐end oligo p‐phenylenevinylene compounds featuring different alkyl substituents (−C4H9 and −C16H33) within a micelle medium. Our findings revealed a correlation between the positioning of the probe molecules within the micelle and the length of the alkyl chains, impacting their self‐assembly tendencies and optical characteristics. The compound with shorter alkyl chains demonstrated a superior affinity towards Hg2+ ions, whereas exposure to the compound with longer alkyl substituent resulted in a color‐changing response with both Cu2+and Hg2+ ions. Intriguingly, the sensitivity towards Hg2+ ions heightened with increasing alkyl chain length. This trend persisted in non‐polar solvents like THF. The capacity to modulate sensing efficacy solely by adjusting the length of the alkyl chains represents a relatively uncommon occurrence in the existing literature. This discovery suggests promising prospects for engineering sensory devices equipped with adaptable sensitivity. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis and properties of a non-benzenoid, 2,6-azulene-based nanoribbon (ANR). The ANR exhibits an optical bandgap of 2.2 eV and 1.7 eV in its neutral and protonated form, respectively. It can be reversibly protonated and has a conductivity of up to 1.5 x 10^3 S cm^-1 for thin films. The study suggests that enhancing the directional alignment of azulene moieties could significantly improve the conductivity of ANR. Further research is needed to explore the potential of these unique nanoribbon structures. [Extracted from the article]

The diphosphination of alkenes through a radical pathway offers a promising approach for the rapid construction of aryl bisphosphines. However, such a synthetic strategy has not been successfully applied to the preparation of alkyl bisphosphines, partially due to the difficulties in the generation of phosphorus‐centered radicals from common alkyl phosphine compounds. We herein demonstrate that this challenge can be overcome by hiring Janus‐faced chlorophosphine as the phosphine source that can act as not only a radical precursor to generate phosphine‐centered radicals but also a radicalphile to capture alkyl radicals. With this novel strategy, a photocatalyzed reductive diphosphination reaction has been established, allowing for a straightforward synthesis of both aryl and alkyl 1,2‐bisphosphines from readily accessible alkenes and chlorophosphines. [ABSTRACT FROM AUTHOR]

A comprehensive review was conducted on the multiple impacts of the Maillard reaction and its products in food processing, along with an exploration of its relationship with food quality and safety. Additionally, a summary of typical innovative reaction product detection technologies was provided. It was noted that this reaction generated brown polymers (e. g., 5-hydroxymethylfurfural) or nitrogen-containing copolymers (melanoidins), inducing browning in food systems, and produced substances (e. g., ketones, aldehydes, alkyl compounds) significantly affecting food flavor. Furthermore, the reaction could not only alter the structural properties of food (e. g., reducing protein fluorescence and surface hydrophobicity) but also create carriers with specific functionalities (e. g., emulsion gelation carriers). While the reaction contributed positively to the generation of antioxidant compounds and the elimination of allergens in food, it may also lead to the formation of potentially harmful substances such as advanced glycation end products, acrylamide, heterocyclic amines, and 5-hydroxymethylfurfural. Currently, major detection techniques for Maillard reaction products include spectroscopy, chromatography, and fluorescence compound characterization methods. Fluorescent compounds, as important intermediates in the Maillard reaction, can be utilized to construct fluorescent probes for real-time monitoring. Future research should delve deeper into the formation mechanisms and influencing factors of harmful substances or further optimize the accuracy and efficiency of these detection methods to provide more comprehensive theoretical support for the continuous development of food processing technology. [ABSTRACT FROM AUTHOR]

In search of new possible uses of cheap lignite from the Kosova Bassin, the surface of lignite powders is modified with alkyl or mixed alkyl‐aryl layers. Modification is performed in aqueous acid solution containing an aryl diazonium salt and an alkyl halide compound in millimolar concentration, in the presence of potassium iodide as a reducing agent at equimolar concentration. Attachment of alkyl films substituted with carboxylic groups and aryl films with nitro or bis‐trifluoromethyl groups is characterized by IRATR and XPS spectroscopy. The formation of a stable interface during the grafting reactions of alkyl and aryl moieties with lignite surface has been confirmed by theoretical calculations. Aryl diazonium salts once chemically or spontaneously reduced are a source of aryl radicals, able to attach chemically to the material surface or to react with alkyl halides by abstracting the halogen atom. If the aryl diazonium salts are unable to graft to the coal surface due to steric hindrance, they can, nevertheless, abstract an iodine or bromine atom to generate alkyl radicals that react with the material surface. [ABSTRACT FROM AUTHOR]

The Ti(OPr‐i)4‐mediated three–component condensation of enantiomeric Ellman's amides, dimethylphosphine oxide, and aliphatic, aromatic or heteroaromatic aldehydes proceeds in high yields and diastereoselectivities enabling the rapid, scalable and general asymmetric synthesis of (α‐amino)dimethylphosphine oxide derived compounds bearing alkyl, cycloalkyl or hetaryl group at the chiral carbon atom. Asymmetric synthesis of α‐amino‐α‐polyfluoroalkyl dimethylphosphine oxides was accomplished through diastereoselective addition of dimethylphosphine oxide to enantiomeric Ellman's aldimines, RFCH=NS(O)tert‐Bu (RF=CF3, CHF2, PhCF2). [ABSTRACT FROM AUTHOR]

Synthesis of diverse sterically congested molecules from a single important intermediate is one of the ideal synthetic strategies in organic synthesis. In this paper, we found that γ‐oxoalkyl substituted cyclohexenone derivatives (OAC) possessing a quaternary carbon are a useful key intermediate to derive both congested fused [5,6] rings and spirocycles. For this purpose, we have established an efficient synthetic method to obtain OAC by tertiary alkylation of β‐methylcyclohexenone derivatives using α‐bromocarbonyl compounds as a tertiary alkyl source. The key to the success of this reaction is controlling the reactivity of the dienamine intermediate. While there have been many reports on enamine reactions, dienamine reactions have not been well studied. Herein, we report controlling reactivity of dienamines and molecular diversification from OAC. [ABSTRACT FROM AUTHOR]

Microorganisms can affect coal biodegradation by driving elemental biogeochemical cycling. A detailed description of the sulfur conversion process led by indigenous bacteria during coal degradation is important. This study obtained sulfur-containing compounds conversion bacteria through indoor enrichment and conducted anaerobic culture experiments using coal supplemented with enriched bacteria. The study showed that the addition of enriched bacteria changed the microbial composition, particularly the microbial groups within Pseudomonadota and Bacillota. In addition, the sulfur-containing compounds conversion bacteria increased the pore volume and specific surface area of micropores (<10 nm) and transition pores (10–100 nm), as well changed the content of sulfur-containing organic components including polypeptides, aromatic compounds, alkyl compounds, and thiazoles. The genera related to inorganic sulfur conversion were mainly belonging to Bacillota and Actinomycetota. Additionally, functional genera that can degrade sulfur-containing organic compounds of dibenzothiophenes through the ring-opening of benzene rings were found within Pseudomonadota, Bacillota and Actinomycetota. In summary, organic sulfur-related Pseudomonadota, Bacillota and Actinomycetota and inorganic sulfur-related Bacillota and Actinomycetota detected in this study could accelerate the sulfur-containing compounds conversion and ultimately increase micropores in coal, and this holds great significance for understanding the biogeochemical cycling process of coal. [ABSTRACT FROM AUTHOR]

Research into the use of sodium tetraalkoxyborate salts for different chemical applications including synthetic catalysis, hydrogen storage, or battery applications has been investigated, however, understanding of the structural, thermal and electrochemical properties of these salts has been lacking since the 1950s and 1960s. A review of the synthesis, as well as a thorough characterization using 1H NMR, 11B NMR, 13C{1H} NMR, FTIR, XRD, in situ XRD, DSC-TGA, RGA-MS, TPPA, and EIS has newly identified polymorphic phase changes for Na[B(OMe)4], K[B(OMe)4], Li[B(OMe)4], Na[B(OEt)4], Na[B(OBu)4], and Na[B(OiBu)4]. The crystal structure of K[B(OMe)4] was also solved in I41/a (a = 22.337(2) Å, c = 7.648(3) Å, V = 3815.6(4) Å3, ρ = 1.128(1) g cm−3). Ionic conductivity of the different salts was analyzed, however it was found that the compounds with longer alkyl chains had no measurable ionic conductivity compared to the shorter chained samples, Na[B(OMe)4] and K[B(OMe)4] with 9.6 × 10−8 S cm−1 and 1.6 × 10−7 S cm−1, at 114 °C respectively. [ABSTRACT FROM AUTHOR]

We report the synthesis, structural characterization and magnetic properties of a series of Co(III)/Dy(III) complexes built up from an N-alkyl derivatized amino-alcohol ligand diethanolamine, functionalized with CnH2n+1 alkyl chains (n = 3, 4, 6, 8 and 10). While n = 3 afforded a butterfly {Co III2 Dy III2 } core, the other alkyl chains (n = 4, 6, 8) afforded hexanuclear triangle-in-triangle {Co III3 Dy III3 } complexes as shown by single-crystal X-ray determinations. Infrared spectroscopy allows us to characterize the C10 derivative complex, which did not crystallize. Magnetic ac susceptibility data collected below 10 K at driving frequencies up to 10 kHz under zero-dc field and up to 1 T provide insight into the SMM behaviour of the studied complexes. The characteristic time of the magnetization dynamics can be understood in terms of the competing Raman, Direct and Orbach-like mechanisms. A relationship between the magnetization dynamics within the family of complexes and the increasing alkyl chain length is discussed. [ABSTRACT FROM AUTHOR]

Background. As a result of studying the synthesis and biological activity of condensed heterocyclic compounds, new drugs have been developed, including derivatives of 3-alkyl-2- methylquinazolin-4-one, and their bioactive derivatives have been identified. The development of new drugs based on them is relevant. Purpose. Development of a method for the synthesis of initial 2-methylquinazolin-4-ones by heterocyclization reaction and, on their basis, the synthesis of 3(H)-substituted 2-methylquinazolin-4-ones in the presence of alkylating agents. Determination of the structures of the obtained substances using IR, ¹H and 13C NMR methods. Methodology. 3-alkyl 2-methylquinazolin-4-ones were synthesized on the basis of 2- methylquinazolin-4-one (2,3-dimethylquinazolin-4-one and other compounds, they were studied by physical methods: IR, 1H and 13C NMR, factors influencing on the course of reactions. Originality. An improved method for the synthesis of 2-methylquinazolin-4-one has been developed using a heterocyclization reaction. New representatives of alkyl compounds have been synthesized. Findings. A method for the synthesis of 2-methylquinazolin-4-one with high yields has been developed, and new derivatives of 3-alkyl-2-methylquinazolin-4-ones based on this substance have been synthesized. Their structure has been studied by physical methods, and their compliance with the proposed structure has been proven. [ABSTRACT FROM AUTHOR]

Anion exchange membranes have aroused much interest for use in electrolyzers and alkaline fuel cells. In this work, two double‐charged anion exchange membranes based on poly(2,5‐benzimidazole) and poly(vinylbenzyl chloride) prepared by the casting method are reported. The effect of two different quaternizing agents based on 1,4‐diazabicyclo[2.2.2]octane (DABCO) was evaluated. These membranes were characterized by means of Fourier transform infrared spectroscopy, SEM, TGA, water contact angle, swelling ratio, KOH and water uptake, ionic exchange capacity and ionic conductivity. The results showed that the length of the alkyl chain has a strong effect on the membrane properties. A good performance in a zero‐gap water alkaline electrolyzer was obtained for the membrane based on the butyl derivate of DABCO (BDABCO). © 2023 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

A new series of bent-shaped liquid crystals containing a triazole ring were synthesised and characterised at ambient and elevated temperatures. The triazole-cored and bent liquid crystals possess a flexible alkyl chain at one terminal, while the other side of the core is connected by a laterally ethoxy Schiff base consisting of a CN-biphenyl moiety. The evaluation on optical and thermal properties was carried out by polarising optical microscope and differential scanning microscope which revealed the length of the alkyl chain, –CnH2n + 1, that influenced the mesophase and the related clearing temperatures (Tc). Whilst the compounds with higher number of n possess lower Tc points, the presence of SmA phase seemed to be more favourable for the compounds in which the alkyl chain length was n ≥ 12. This observation can be associated with its bending angle and charge distributions along the two arms of which the interaction between the opposite counterparts of both arms in these bent-liquid crystals would promote the formation of SmA phase. The computational calculations based on density functional theory were performed to further support the transition from non-mesomorphic to SmA phases upon the increase in alkyl chain length (n), dipole moment and polarity which contribute to its stability. [ABSTRACT FROM AUTHOR]

Three homoleptic Hg(S2CNR2)2, for R = ethyl (1), isobutyl (2), and cyclohexyl (3), compounds apparently exhibit a steric-dependent supramolecular association in their crystals. The small group in 1 allows for dimer formation via covalent Hg–S interactions through an eight-membered {–HgSCS}2 ring as the dithiocarbamato ligands bridge centrosymmetrically related Hg atoms; intradimer Hg···S interactions are noted. By contrast, centrosymmetrically related molecules in 2 are aligned to enable intermolecular Hg···S interactions, but the separations greatly exceed the van der Waals radii. The large group in 3 precludes both dimerization and intermolecular Hg···S interactions. Computational chemistry indicates that the potential region at the Hg atom is highly dependent on the coordination geometry about the Hg atom. Intramolecular (1) and intermolecular (2) spodium bonding (SpB) is demonstrated. Even at separations approaching 0.4 Å beyond the sum of the assumed van der Waals radii, the energy of the stabilization afforded by the structure directs SpB in 2 amounts to approximately 2.5 kcal/mol. A natural bond orbital (NBO) analysis points to the importance of the LP(S) → σ*(Hg–S) charge transfer and to the dominance of the dispersion forces and electron correlation to the SpB in 2. [ABSTRACT FROM AUTHOR]

Nowadays, organosulfur compounds provide new options in the development of full organic ion batteries. However, many drawbacks (such as kinetics limitations during the reversible oxidation of disulfides with cleavage of S–S bond, as well as solubility in non-aqueous electrolytes) make their commercialization difficult. Herein, a new concept for the design of organosulfur compounds with regulated redox properties and limited solubility is proposed. As a proof-of-concept, we designed peri-disulfo-substituted 1,8-naphthalimide derivatives, in which the alkyl chain length and halogen substituents (Cl or Br) at positions 3 and 6 are varied. The compounds were synthesized by an originally developed procedure starting from tetrahalonaphthalic anhydride via nucleophilic substitution at both peri-positions in the respective imide. Using ionic liquid electrolyte, it was found that the new peri-dithiolo-1,8-naphthalimides can participate in n- and p-type redox reactions at about 2.0 V and above 4.0 V vs. Li/Li+, respectively. The redox potentials are sensitive mainly to whether Cl or Br substituents are available in the molecule architecture, while the alkyl chain length determines the kinetics of the redox reactions. Among all compounds, the chloro-substituted compound with the shorter alkyl chain displays the best kinetics for both low- and high-voltage redox reactions. [ABSTRACT FROM AUTHOR]

This research investigated the aging degradation of anhydride-cured epoxy asphalt (EA) subjected to ultraviolet (UV) exposure. A UV accelerated aging test was applied to age EA binders with graduated asphalt contents at 25%, 35%, 45%, 55%, and 65%. The effects of aging on the mechanical, chemical properties, and microstructure of EA were investigated. Results show that the more asphalt is introduced, the higher the mass loss rate of the EA binders, and the more prominent the decrease in elongation and fracture energy during aging. The storage modulus and hardness of EA binders increased after aging. The tensile strength and glass transition temperature of EA binder with 25%-45% asphalt content decreased, while those of EA binder with 55%-65% asphalt content increased. Besides, several carbonyl compounds formation, hydroperoxides formation, and loss of alkyl compounds were observed. Also, when the asphalt content was lower than 45%, holes and microcracks appeared on the surface, while above 45% asphalt content wrinkles. Degradation of the resin network in EA binders was evident by the loss of ester compounds and the microcrack of the resin phase. Overall, the resin network can reduce UV damage to asphalt and improve the photo-oxidative aging resistance of EA materials. [ABSTRACT FROM AUTHOR]

BACKGROUND: α‐Ketothioamides play a vital role in the fields of medicine and biology. There are many α‐ketothioamide synthesis pathways, but in general, most current methods involve either conventional heating in solvent conditions or using non‐recyclable catalysts. Thus, our work investigated the preparation of α‐ketothioamides under solvent‐free sonication using magnetic nanoparticle‐immobilized chlorozincate ionic liquid as a catalyst. The desired products were purified by chromatography columns and characterized using 1H NMR and 13C NMR. RESULTS: In this study, Lewis acidic ionic liquid grafted onto magnetic nanoparticles (Fe3O4@IL‐ZnCl2) was used as an effective heterogeneous catalyst for the generation of a variety of α‐ketothioamide derivatives. The optimized conditions were methyl ketone (1.0 mmol), amine (1.2 mmol), S8 (1.2 mmol) and Fe3O4@IL‐ZnCl2 (15 mg) under solvent‐free sonication at 80 °C for 5 h, and the crude products were obtained in a 34–94% isolated yield. Then, this procedure was successfully applied to a wide range of aryl and alkyl ketone compounds. Besides, there was only a slight loss in catalytic activity in three consecutive cycles, indicating the reusability and stability of the catalytic system. CONCLUSIONS: We have successfully designed a novel protocol for the generation of α‐ketothioamide derivatives from aryl/alkyl methyl ketones, amines, and elemental sulfur catalyzed by chlorozincate ionic liquid‐coated magnetic Fe3O4 nanoparticles. The reaction proceeded via a mild, efficient, solvent‐free sonication accompanied by a well‐reactive catalyst, which is easily separated and reusable. Besides, a feasible mechanism is presented. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

This article discusses the use of various compounds, such as diazo compounds, N-arylsulfonylhydrazones, and ylides, in transition-metal-free insertion reactions with organoboronic acids and their derivatives. These reactions are important for constructing C-C bonds or C-X (X = H, B) bonds. The article provides examples of specific reactions and their mechanisms, as well as the synthesis of various compounds through these reactions. It also briefly introduces the academic career and research interests of W. Jefford, who focuses on catalytic metal carbene transformations. [Extracted from the article]

Herein, we introduce a variety of azopolyesters (azobenzene‐based polyesters) with remarkable intrinsic crystallinity and photoinduced reversible solid‐to‐liquid transition abilities from copolymerization of azobenzene‐based epoxides with cyclic anhydrides. The length of the soft alkyl side‐chain inlaid with azobenzenes and stereoregularity of main‐chain of azopolymers have tremendous effects on crystallization properties of the resulting polyesters with melting temperature (Tm) in the range of 51–251 °C. Moreover, some of azopolyesters possess excellently photoinduced reversible solid‐to‐liquid transition performance thanks to trans‐cis photoisomerization of azobenzenes. Trans‐azopolyesters are yellow solids with Tms or glass transition temperatures (Tgs) above room temperature, whereas cis‐polymers are red liquids with Tgs below −20 °C. These azopolyesters could be applied as novel light‐switchable adhesives for quartz/quartz, wood/wood and quartz/wood adhesion, with the strength in the range of 0.73–0.89 MPa for trans‐polymers. Conversely, the adhesion strength of liquefied cis‐azopolyesters generated from the irradiation of trans‐polymers by UV light was about 0.1 MPa, which shows light enable to control the adhesion process with high spatiotemporal resolution. [ABSTRACT FROM AUTHOR]

Cross‐electrophilic coupling of various benzyl sulfonium salts with Callyl−O electrophiles is described using a simple Co−Mn catalytic system. This catalytic system is able to activate both the stable Csp3−S bond of sulfonium salts and the Csp3−O bond of allylic acetate or ether under mild reaction conditions to form various functionalized alkyl olefinic compounds. Allyl methyl ethers were employed for the first time in transition metal‐catalyzed cross‐electrophilic coupling to build Csp3−Csp3 bonds. Preliminary mechanistic studies suggested the involvement of benzyl radicals generated from C−S bond cleavage through a single electron transfer. [ABSTRACT FROM AUTHOR]

Bis(phenolate) ligands with benzimidazole‐2‐ylidene (L1) and tetrahydropyrimidine‐2‐ylidene (L2) linkers proved to be suitable coordination environments for the synthesis of isolable Sc3+ chloro and alkyl complexes. The treatment of Sc(CH2SiMe3)3(THF)2 with equimolar amounts of [L1,2H3]Cl afforded chloro complexes L1,2ScCl(solv)2 (solv=THF, Py) in 76–85 % yields. L1,2ScCl(THF)2 were also prepared by the salt metathesis reactions of ScCl3 with [L1,2]Na2 generated from [L1,2H3]Cl and 3 equiv. of NaN(SiMe3)2 (−40 °C, THF) and isolated in somewhat lower yields (68–73 %). L2ScCl(THF)2 was subjected to the alkylation reaction with LiCH2SiMe3 affording alkyl derivative [L2Sc(CH2SiMe3)]2. This compound can be alternatively prepared by the subsequent reactions of [L2H3]Cl with equimolar amount of NaN(SiMe3)2 and Sc(CH2SiMe3)3(THF)2. In the dimeric alkyl compound [L2Sc(CH2SiMe3)]2, one of the phenoxide groups of the dianionic ligand is coordinated to one scandium center, while the second one features μ‐bridging coordination with two metal centers. [ABSTRACT FROM AUTHOR]

Ion beam induced luminescence (IBIL) analysis of adsorbents containing Eu complexes was carried out using a 3-MV single-ended accelerator and an azimuthally varying field cyclotron to evaluate structures of complexes in an extraction chromatography. Some adsorbents were prepared by impregnating a styrene-divinylbenzene copolymer-coated porous silica particle (SiO 2 -P) with extractants. The IBIL spectra of Eu complexes in the adsorbents produced some differences depending on the kinds of extractants. The experimental results imply that the difference in the IBIL spectra of Eu complexes in the adsorbents is caused by the difference in the structures. The only clear luminescence peak in the alkyl diamide amine (ADAAM) with n -octyl and 2-ethylhexyl alkyl chains (ADAAM(Oct, N (EH))) adsorbent was not observed by H+ ion beam irradiation. Meanwhile, the luminescence of Eu could be detected by irradiation of an Ar8+ ion beam. The luminescence of Eu complexes is presumed to be easily detected by high linear energy transfer (LET) beam irradiation. The symmetric properties of Eu complexes were evaluated with the luminescence due to the 5D 0 → 7F 2 transition, and it is implied that ADAAM with 2-ethylhexyl alkyl chains (ADAAM(EH, N (EH))) is a high asymmetry property. The luminescence intensity of Eu complexes in the adsorbent decreased with the ion beam irradiation because extractants were damaged by the ion beam. This phenomenon was clearly observed by irradiation of high LET ion beam, Ar8+. [ABSTRACT FROM AUTHOR]

Visible-Light-Responsive Nano CuO/ZnO Photocatalyst for Chan-Lam Coupling Reaction and Aerobic C(sp3)-H Bond Oxidation Semiconductor, Chan-Lam reaction, heterogeneous photocatalyst, C(sp 3)-H bond oxidation, gram-scale synthesis Keywords: semiconductor; heterogeneous photocatalyst; Chan-Lam reaction; C(sp 3)-H bond oxidation; gram-scale synthesis EN semiconductor heterogeneous photocatalyst Chan-Lam reaction C(sp 3)-H bond oxidation gram-scale synthesis 2495 2502 8 07/31/23 20230817 NES 230817 Graph The emergence of photocatalysts can be described as one of the most important developments in the chemistry world. In summary, we have reported a convenient and practical photochemical method for the Chan-Lam coupling and C(sp SP 3 sp )-H bond oxidation reactions using nano CuO/ZnO as a sustainable and cost-effective photocatalyst. [Extracted from the article]

The chemoselectivity between S‐oxidation and hydrogen atom transfer (HAT) from C−H bonds has been investigated in the oxidations of a series of aryl sulfides, alkyl aromatic compounds and benzylic alcohols promoted by the iron(IV)‐oxo complex [(N4Py)FeIV(O)]2+ (N4Py: N,N‐bis(2‐pyridylmethyl)‐N‐bis(2‐pyridyl)‐methylamine) either alone or in the presence of the N‐hydroxyphthalimide (NHPI) mediator via kinetic and product studies. Kinetic analyses indicate a generally higher reactivity of [(N4Py)FeIV(O)]2+ for S‐oxidation process while HAT is favored in the reactions promoted by phthalimide‐N‐oxyl radical (PINO) deriving from NHPI oxidation. Product analysis in intermolecular competitive oxidations confirms the kinetic results with sulfoxides obtained as major products in the oxidation promoted by [(N4Py)FeIV(O)]2+. Conversely, when NHPI is employed as a mediator, significant differences in terms of chemoselectivity are observed, and HAT‐derived products are obtained in higher yields which translate into an inversion of selectivity in the case of the substrates containing activated C−H bonds like diphenylmethane, triphenylmethane and benzylic alcohols. A similar change of chemoselectivity is also observed in the oxidation of aromatic substrates containing both a sulfur atom and α to OH benzylic C−H bonds, with the sulfoxide product more abundant in the absence of NHPI and carbonyl products prevailing with the [(N4Py)FeIV(O)]2+/NHPI system. [ABSTRACT FROM AUTHOR]

Despite the growing importance of fluorinated organic compounds in pharmaceuticals, agrochemicals, and materials science, the introduction of fluorine into organic molecules is still a challenge, and no catalytic fluorocarbonylation of aryl/alkyl boron compounds has been reported to date. Herein, we present the development of palladium and phosphine synergistic redox catalysis of fluorocarbonylation of potassium aryl/alkyl trifluoroborate. Trifluoromethyl arylsulfonate (TFMS), which was used as a trifluoromethoxylation reagent, an easily handled and bench-scale reagent, has been employed as an efficient source of COF2. The reaction operates under mild conditions with good to excellent yields and tolerates diverse complex scaffolds, which allows efficient late-stage fluorocarbonylation of marked small-molecule drugs. Mechanistically, the key intermediates of labile Brettphos-Pd(II)-OCF3 complex and difluoro-Brettphos were synthesized and spectroscopically characterized, including X-ray crystallography. A detailed reaction mechanism involving the synergistic redox catalytic cycles Pd(II)/(0) and P(III)/(V) was proposed, and multifunction of phosphine ligand was identified based on 19F NMR, isotope tracing, synthetic, and computational studies. Despite the growing importance of fluorinated organic compounds introduction of fluorine into organic molecules is still challenging. Here, the authors present the development of palladium and phosphine synergistic redox catalysis of fluorocarbonylation of potassium aryl/alkyl trifluoroborate. [ABSTRACT FROM AUTHOR]

N‐(difluoromethyl)amino (−NCF2H) compounds are of great interest given their unique and underexplored physiochemical properties. The lack of structural diversity in NCF2H compounds is likely due in part to the shortage of protocols for efficient installation. Presented herein is a new shelf‐stable pyridinium reagent that enables the direct installation of the N‐(difluoromethyl)sulfonamide moiety [N(Ts)CF2H)] onto (hetero)arenes and alkenes for the diversification of aryl and alkyl NCF2H compounds. The described protocol utilizes blue light photoredox catalysis and displays broad functional group tolerance with excellent chemoselectivity. Additional transformations and applicability towards a photoredox continuous flow protocol are also demonstrated. [ABSTRACT FROM AUTHOR]

The modification of polymer chain ends is important in order to produce highly functional polymers. A novel chain-end modification of polymer iodides (Polymer-I) via reversible complexation-mediated polymerization (RCMP) with different functionalized radical generation agents, such as azo compounds and organic peroxides, was developed. This reaction was comprehensively studied for three different polymers, i.e., poly (methyl methacrylate), polystyrene and poly (n-butyl acrylate) (PBA), two different functional azo compounds with aliphatic alkyl and carboxy groups, three different functional diacyl peroxides with aliphatic alkyl, aromatic, and carboxy groups, and one peroxydicarbonate with an aliphatic alkyl group. The reaction mechanism was probed using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The combination of PBA-I, iodine abstraction catalyst and different functional diacyl peroxides enabled higher chain-end modification to desired moieties from the diacyl peroxide. The dominant key factors for efficiency in this chain-end modification mechanism were the combination rate constant and the amount of radicals generated per unit of time. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience 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.)

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell 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.)

In this study, sulfonic acid functionalized polystyrene coated coal fly ash catalyst (CFA@PS-SO3H) was designed and prepared by the post-synthesis method, which exhibited excellent catalytic performance for esterification of levulinic acid (LA) to afford alkyl levulinates. Four significant factors, including reaction time, catalyst dosage, alcohol-to-acid molar ratio and reaction temperature were evaluated systematically. Response surface methodology based on Box-Behnken design (BBD) was carried out to determine the optimal parameters. The maximum yield could reach 99.6% under the mild conditions. Furthermore, kinetics of the esterification reaction between levulinic acid and n-butanol were analyzed and the activation energies of the first and second step of esterification reaction were found to 52.18 and 59.81 kJ/mol, respectively. The CFA@PS-SO3H also showed high catalytic activity for the esterification of levulinic acid with other linear alcohols, which made it a low cost, environmentally friendly and promising solid catalyst for the synthesis of alkyl levulinates. [ABSTRACT FROM AUTHOR]

The feedstock adaptability and product selectivity of catalyst are very important for heavy oil hydrocracking. Considering that the components of heavy oil are mainly composed of aromatic compounds and alkyl compounds, Mo aryl-alkyl-dithiophosphate (Mo-Ar/R) with both benzyl and n-butyl was efficiently prepared based on the preparation method of Mo dialkyl-dithiophosphate (Mo-R) with only n-butyl whose high hydrogenation activity has been proved to improve the structural similarity to feedstock. Fourier transform infrared (FTIR) analysis, elemental analysis and oil solubility study were carried out on Mo-Ar/R and Mo-R. X-Ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscopy (SEM) and polarized microscope were used to obtain the structural and morphological information of MoS 2 catalysts. Mo-Ar/R and Mo-R were evaluated in the hydrocracking of atmospheric residue ultra heavy oil (feedstock A), high sulfur vacuum residue (feedstock B) and coal tar oil (feedstock C) at 430 ℃ with an initial hydrogen pressure of 7 MPa for various reaction times, respectively. The results showed that the coexistence of benzyl and n-butyl led to better oil solubility of Mo-Ar/R, smaller size, lower stacking number and shorter slab length of the resulting MoS 2 catalysts. Compared with Mo-R, Mo-Ar/R increased the valuable product yields during hydrocracking of feedstock A, feedstock C and feedstock B by 1.33 wt%, 3.53 wt% and 3.97 wt%, decreased the coke yields by 0.21 wt%, 0.40 wt% and 0.51 wt% and decreased the gas yields by 0.65 wt%, 0.97 wt% and 1.19 wt%, respectively. The initial hydrogen consumption rates and TOFs obtained in the presence of Mo-A/R are higher than that obtained in the presence of Mo-R. The performance difference between Mo-Ar/R and Mo-R seemed to be related to the contents of saturates of the different feedstocks. The coexistence of benzyl and n-butyl was proved to lead to the better feedstock adaptability and product selectivity of Mo-Ar/R compared with Mo-R due to the better structural similarity. [Display omitted] • Mo-A/R with both benzyl and n-butyl was efficiently prepared based on the preparation method of Mo-R with only n-butyl. • The effect of the coexistence of benzyl and n-butyl on structure, morphology and performance of MoS 2 were investigated. • The coexistence of benzyl and n-butyl was proved to lead to the better feedstock adaptability and product selectivity. [ABSTRACT FROM AUTHOR]

The copper‐catalyzed enantioselective radical difunctionalization of alkenes from readily available alkyl halides and organophosphorus reagents possessing a P−H bond provides an appealing approach for the synthesis of α‐chiral alkyl phosphorus compounds. The major challenge arises from the easy generation of a P‐centered radical from the P−H‐type reagent and its facile addition to the terminal side of alkenes, leading to reverse chemoselectivity. We herein disclose a radical 1,2‐carbophosphonylation of styrenes in a highly chemo‐ and enantioselective manner. The key to the success lies in not only the implementation of dialkyl phosphites with a strong bond dissociation energy to promote the desired chemoselectivity but also the utilization of an anionic chiral N,N,N‐ligand to forge the chiral C(sp3)−P bond. The developed Cu/N,N,N‐ligand catalyst has enriched our library of single‐electron transfer catalysts in the enantioselective radical transformations. [ABSTRACT FROM AUTHOR]

A protocol for the generation of allylmagnesium reagents from 2‐aryl‐1,3‐dienes was developed using magnesium hydride (MgH2) that is generated in situ by solvothermal treatment of sodium hydride (NaH) and magnesium iodide (MgI2) in tetrahydrofuran (THF). Downstream functionalization of the resulting allylmagnesium reagents with carbonyl compounds or alkyl (pseudo)halides delivers branched products having an allylic quaternary carbon center, whereas that with chlorosilanes resulted in formation of linear allylsilanes in regio and stereoselective manners. Further derivatizations of the homoallylic alcohols and allylsilanes were also demonstrated. [ABSTRACT FROM AUTHOR]