Metal-free synthesis of 3-chalcogen benzo[b]furans via an iodine-mediated electrophilic cyclisation of 2-alkynylanisoles
作者:Mei Xu、Xiao-Hong Zhang、Ping Zhong
DOI:10.1016/j.tetlet.2011.10.045
日期:2011.12
An efficient and metal-free method was developed to synthesize 3-chalcogen benzo[b]furans via the iodine-mediatedelectrophilic cyclisation of 2-alkynylanisoles with disulfides or diselenides. In the presence of I2, various 3-sulfenylbenzofurans or 3-selenenylbenzofurans were obtained in moderate to high yields.
通过用二硫化物或二硒化物通过碘介导的2-炔基茴香醚的亲电亲电环化反应,开发了一种高效且无金属的方法来合成3-硫属元素苯并[ b ]呋喃。在I 2的存在下,以中等至高产率获得了各种3-亚磺酰基苯并呋喃或3-硒代苯并呋喃。
AgNO2-catalyzed radicalcyclization of 2-alkynylanisoles (or 2-alkynylthioanisoles), Se powder, and arylboronic acids. This method enables the construction of a benzofuran (benzothiophene) ring, two C-Se bonds, and a C-O(S) bond as well as the cleavage of a C-O(S) bond in a single step. Preliminary mechanistic studies imply that the AgNO2-catalyzed cyclization proceeds via an aryl selenium radical intermediate