School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong Province 529090, China.
College of Chemistry, Guangdong University of Petrochemical Technology, Guangdu 2nd road, Maoming, Guangdong Province 525000, China.
J Org Chem. 2020 Oct 16;85(20):13037-13049. doi: 10.1021/acs.joc.0c01733. Epub 2020 Sep 29.
An environmentally sustainable strategy for the chemoselective heterocyclization of bromoenynes through a transition-metal-free sulfuration/cyclization process is reported. Using inexpensive and safe EtOCSK as a thiol surrogate and tetrabutylphosphonium bromide and HO as a mixed solvent, the reaction provided a range of substituted thiophenes in moderate to good yields. In addition, 2,3,4,5-tetrasubstituted thiophenes were able to be prepared under mild reaction conditions by electrophilic heterocyclization with NHI and EtOCSK in good yields.
本文报道了一种通过无过渡金属硫化/环化过程实现溴炔的化学选择性杂环化的环境可持续策略。使用廉价且安全的 EtOCSK 作为硫醇替代物，以及四丁基溴化膦和 HO 作为混合溶剂，该反应以中等至良好的收率提供了一系列取代的噻吩。此外，通过 NHI 和 EtOCSK 的亲电杂环化，在温和的反应条件下，也能够以良好的收率制备 2,3,4,5-四取代噻吩。
