20893-30-5Relevant articles and documents
From Stoichiometric Reagents to Catalytic Partners: Selenonium Salts as Alkylating Agents for Nucleophilic Displacement Reactions in Water
Martins, Nayara Silva,ángel, Alix Y. Bastidas,Anghinoni, Jo?o M.,Lenard?o, Eder J.,Barcellos, Thiago,Alberto, Eduardo E.
supporting information, p. 87 - 93 (2021/11/03)
The ability of chalcogenium salts to transfer an electrophilic moiety to a given nucleophile is well known. However, up to date, these reagents have been used in stoichiometric quantities, producing a substantial amount of waste as byproducts of the reaction. In this report, we disclose further investigation of selenonium salts as S-adenosyl-L-methionine (SAM) surrogates for the alkylation of nucleophiles in aqueous solutions. Most importantly, we were able to convert the stoichiometric process to a catalytic system employing as little as 10 mol % of selenides to accelerate the reaction between benzyl bromide and other alkylating agents with sodium cyanide in water. Probe experiments including 77Se NMR and HRMS of the reaction mixture have unequivocally shown the presence of the selenonium salt in the reaction mixture. (Figure presented.).
NHC-catalyzed silylative dehydration of primary amides to nitriles at room temperature
Ahmed, Jasimuddin,Hota, Pradip Kumar,Maji, Subir,Mandal, Swadhin K.,Rajendran, N. M.
supporting information, p. 575 - 578 (2020/01/29)
Herein we report an abnormal N-heterocyclic carbene catalyzed dehydration of primary amides in the presence of a silane. This process bypasses the energy demanding 1,2-siloxane elimination step usually required for metal/silane catalyzed reactions. A detailed mechanistic cycle of this process has been proposed based on experimental evidence along with computational study.
Preparation method of non-steroidal anti-inflammatory drug tiaprofenic acid
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Paragraph 0039; 0040, (2018/03/26)
The invention relates to a preparation method of non-steroidal anti-inflammatory drug tiaprofenic acid. The preparation method includes: taking 2-chloromethyl thiophene as a starting raw material; synthesizing thiophene-2-acetonitrile by allowing 2-chloromethyl thiophene to react with trimethylsilyl cyanide; allowing thiophene-2-acetonitrile to react with dimethyl carbonate for methylation prior to cyan-hydrolysis; finally, performing benzoyl chloroformylation reaction to obtain tiaprofenic acid. The preparation method has the advantages that rare, valuable and dangerous materials are replacedwith common, cheap and safe raw materials, serious pollution problems are avoided, and production cost is greatly reduced; in addition, the process adopted in the method is short in route, short in reaction period, stable in reaction condition and high in yield which can be up to 90%, the product obtained is high in purity which can reach above 99%, and the preparation method is applicable to industrial production.
