The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Wei Kang - One of the best experts on this subject based on the ideXlab platform.
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n heterocyclic carbene catalyzed Cyanomethylation of aldehydes with tmsan
ChemInform, 2012Co-Authors: Yecheng Fan, Wanfu Sun, Wei KangAbstract:A broad spectrum of aromatic aldehydes, 2 aliphatic aldehydes and ketone (VI) are subjected to the title reaction to produce the synthetically important building blocks with moderate to good yields.
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n heterocyclic carbene catalyzed Cyanomethylation of aldehydes with tmsan
Tetrahedron Letters, 2012Co-Authors: Yecheng Fan, Wanfu Sun, Wei KangAbstract:Abstract N-Heterocyclic carbenes (NHCs) have been served as efficient catalysts for Cyanomethylation of carbonyl compounds. In the presence of 5 mol % NHC, various aldehydes and 2,2,2-trifluoroacetophenone reacted with trimethylsilylacetonitrile (TMSAN) to give β-hydroxynitriles in moderate to high yields.
Muhammad Siddique Ahmad - One of the best experts on this subject based on the ideXlab platform.
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cu catalyzed Cyanomethylation of imines and α β alkenes with acetonitrile and its derivatives
RSC Advances, 2021Co-Authors: Muhammad Siddique Ahmad, Atique AhmadAbstract:We describe copper-catalyzed Cyanomethylation of imines and α,β-alkenes with a methylnitrile source and provide an efficient route to synthesize arylacrylonitriles and β,γ-unsaturated nitriles. This method tolerates aliphatic and aromatic alkenes substituted with a variety of functional groups such as F, Cl, Br, Me, OMe, tert-Bu, NO2, NH2 and CO2H with good to excellent yields (69–98%). These systems consist of inexpensive, simple copper catalyst and acetonitrile with its derivatives (α-bromo/α-iodo-acetonitrile) and are highly applicable in the industrial production of acrylonitriles.
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recent advances in c cn and c h bond activation of green nitrile mecn for organo complexation cyanation and Cyanomethylation
New Journal of Chemistry, 2020Co-Authors: Muhammad Siddique Ahmad, Indra Neel PulidindiAbstract:The use of green and inexpensive organic nitrile (MeCN) as a cyano and cyano-methyl source for organo-complexation, cyanation, and Cyanomethylation is reviewed. In recent decade, a lot of developments have been made to realize the possibility of using a green cyanide source (MeCN) for cyanation, and this CN source has been used as, for example, a slow dosage cyanide source that could solve the problem of using metal cyanides (K4[Fe(CN)6], Zn(CN)2, KCN, CuCN, NaCN), which (1) tend to cause rapid deactivation of the catalyst and (2) are notoriously toxic, producing highly toxic HCN gas in reactions. In view of these problems, here we attempted to discuss new catalyst systems to achieve the cyanation of various aromatic hydrocarbons, such as aryl halides, aryl boronic acids, aryl carboxylic acids, indoles, diazoarenes, aryl alkynes, aryl sulfonamides, and directing group substituted arenes, under variety of reaction parameters. Moreover, acetonitrile is used as the carbon pro-nucleophile in C–C bond formation, which involves complications usually associated with the catalyst active mode or its resting state. This review demonstrates a set of innovations for practical usage via direct complexation, cyanation and Cyanomethylation methodologies.
Selcuk Essiz - One of the best experts on this subject based on the ideXlab platform.
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a computational study for the reaction mechanism of metal free Cyanomethylation of aryl alkynoates with acetonitrile
RSC Advances, 2021Co-Authors: Selcuk EssizAbstract:A computational study of metal-free Cyanomethylation and cyclization of aryl alkynoates with acetonitrile is carried out employing density functional theory and high-level coupled-cluster methods, such as coupled-cluster singles and doubles with perturbative triples [CCSD(T)]. Our results indicate that the reaction of aryl alkynoates with acetonitrile in the presence of tert-butyl peroxybenzoate (TBPB) under metal-free conditions tends to proceed through Cyanomethylation, spirocyclization and ester migration of the kinetically favoured coumarin derivatives. 1,2-Ester migration in the spiro-radical intermediate 10 does not proceed via the formation of the carboxyl radical 11 suggested by Sun and co-workers. Our results also demonstrate that the t-butoxy radical is substantially responsible the formation of the cyanomethyl radical by the abstraction of a hydrogen atom from acetonitrile.
Atique Ahmad - One of the best experts on this subject based on the ideXlab platform.
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cu catalyzed Cyanomethylation of imines and α β alkenes with acetonitrile and its derivatives
RSC Advances, 2021Co-Authors: Muhammad Siddique Ahmad, Atique AhmadAbstract:We describe copper-catalyzed Cyanomethylation of imines and α,β-alkenes with a methylnitrile source and provide an efficient route to synthesize arylacrylonitriles and β,γ-unsaturated nitriles. This method tolerates aliphatic and aromatic alkenes substituted with a variety of functional groups such as F, Cl, Br, Me, OMe, tert-Bu, NO2, NH2 and CO2H with good to excellent yields (69–98%). These systems consist of inexpensive, simple copper catalyst and acetonitrile with its derivatives (α-bromo/α-iodo-acetonitrile) and are highly applicable in the industrial production of acrylonitriles.
Calin Jianu - One of the best experts on this subject based on the ideXlab platform.
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synthesis of nonionic anionic colloidal systems based on alkaline and ammonium β nonylphenol polyethyleneoxy n 3 20 propionates dodecylbenzenesulfonates with prospects for food hygiene
Chemistry Central Journal, 2012Co-Authors: Calin JianuAbstract:The main objective of this work was to obtain a binary system of surface-active components (nonionic soap – alkaline and/or ammonium dodecylbenzenesulfonate) with potential competences in food hygiene, by accessing a scheme of classical reactions (cyanoethylation, total acid hydrolysis and stoichiometric neutralization with inorganic alkaline and/or organic ammonium bases) adapted to heterogeneously polyethoxylated nonylphenols (n = 3-20). In the processing system mentioned, dodecylbenzenesulfonic acid, initially the acid catalyst for the exhaustive hydrolysis of β-nonylphenolpolyethyleneoxy (n = 3-20) propionitriles, becomes together with the nonionic soap formed the second surface-active component of the binary system. In the reaction scheme adopted the influence of the main operating (duration, temperature, molar ratio of reagents) and structural parameters (degree of oligomerization of the polyoxyethylene chain) on the processing yields for the synthetic steps was followed. The favorable role of the polyoxyethylene chain size is remarked, through its specific conformation and its alkaline cations sequestration competences on the yields of cyanoethylation, but also the beneficial influence of phase-transfer catalysts in the total acid hydrolysis step. The chemical stability of dodecylbenzenesulfonic acid (DBSH) at the temperature and strongly acidic pH of the reaction environment is confirmed. The controlled change of the amount of DBSH in the final binary system will later confer it potential colloidal competences in food hygiene receipts. The preliminary synthetic tests performed confirmed the prospect of obtaining a broad range of useful colloidal competences in various food hygiene scenarios.
