Acharya Anand, Vijay Kumar S, Saraiah B, Ila H
New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research , Jakkur, Bangalore 560064, India.
J Org Chem. 2015 Mar 6;80(5):2884-92. doi: 10.1021/acs.joc.5b00032. Epub 2015 Feb 17.
An efficient one-pot synthesis of highly functionalized multisubstituted benzo[b]thiophenes and their hetero-fused analogues, such as thieno[2,3-b]thiophenes, indolo[2,3-b]thiophenes, and pyrazolo[3,2-c]thiophenes, has been reported. The overall strategy involves sequential base-mediated condensation of 2-bromohet(aryl)acetonitrile precursors with (het)aryl/alkyl dithioesters or other thiocarbonyl species such as dimethyl trithiocarbonate, S-methyl xanthates, methyl N-imidazolyl dithioate, N-alkyl dithiocarbamate, and phenyl isothiocyanate, followed by intramolecular copper-catalyzed arylthiolation of in situ generated enethiolates, furnishing a broad range of 2-functionalized 3-cyanobenzo[b]- and/hetero-fused thiophenes in high yields.
据报道，已实现了一种高效的一锅法合成高官能化多取代苯并[b]噻吩及其杂环稠合类似物，如噻吩并[2,3-b]噻吩、吲哚并[2,3-b]噻吩和吡唑并[3,2-c]噻吩。总体策略包括2-溴代杂（芳基）乙腈前体与（杂）芳基/烷基二硫代酯或其他硫羰基化合物（如三硫代碳酸二甲酯、S-甲基黄原酸酯、N-咪唑基二硫代甲酸甲酯、N-烷基二硫代氨基甲酸盐和异硫氰酸苯酯）的顺序碱介导缩合，随后进行原位生成的烯硫醇盐的分子内铜催化芳基硫醇化反应，以高产率提供多种2-官能化的3-氰基苯并[b]-和/或杂环稠合噻吩。
