Copper-Catalyzed Synthesis of Substituted Benzothiazoles via Condensation of 2-Aminobenzenethiols with Nitriles
摘要:
An efficient and convenient method was developed for the formation of 2-substituted benzothiazoles via a copper-catalyzed condensation of 2-aminobenzenethiols with nitriles. The developed method is applicable to a wide range of nitriles containing different functional groups furnishing excellent yields of the corresponding products.
Lawesson'sreagent acts as an efficient promoter in the solvent-free microwave-assisted synthesis of 2-substituted benzoxazoles from carboxylic acids and 2-aminophenol, and thus, constitutes a general synthetic method for these compounds. This new application of Lawesson'sreagent is valid also for benzothiazoles with very high efficiency level. A variety of aromatic, heteroaromatic and aliphatic carboxylic
Substituted benzothiazoles are synthesized by metal-catalyst-free three-component reactions of o-iodoaniline, quaternary ammonium salt, and sulfur powder in water with moderate-to-excellent yields up to 95%.
Iron-Catalyzed C–H Alkylation of Heterocyclic C–H Bonds
作者:Kaki Raveendra Babu、Nengbo Zhu、Hongli Bao
DOI:10.1021/acs.orglett.6b03287
日期:2017.1.6
An efficient, iron-catalyzed C–H alkylation of benzothiazoles by using alkyl diacyl peroxides and alkyl tert-butyl peresters which are readily accessible from carboxylic acids to synthesize 2-alkylbenzothiazoles is developed. This reaction is environmentally benign and compatible with a broad range of functional groups. Various primary, secondary, and tertiary alkyl groups can be efficiently incorporated
cascade radicalC(sp2/sp3)-S bond cleavage and group-transfer cyclization is disclosed. Triggered by alkyl radicals, varieties of 2-isocyanoaryl thioethers containing aliphatic, aryl, and heteroaromatic groups can be cleaved and precisely reinstalled to give benzothiazole derivatives. Mechanistic studies reveal that the cascade reaction undertakes an intermolecular pathway, and the inner radical sources