A benzo[b]thiophene synthesis by Rh‐catalyzedthree‐component coupling reaction of arylboronic acids, alkynes, and elemental sulfur (S8) is developed. A notable feature of this protocol is that the thienannulation (thiophene annulation) proceeds with high regioselectivity via the sequential alkyne insertion, C−H activation, and then sulfur atom transfer to the metallacycle intermediate. In a similar
开发了通过Rh催化的芳基硼酸,炔烃和元素硫(S 8)的三组分偶联反应合成苯并[ b ]噻吩。该协议的一个显着特征是,噻吩环化(噻吩环化)通过顺序的炔烃插入,CH活化以及随后的硫原子转移至金属环中间体而以高区域选择性进行。可以类似的方式,由母体联芳基硼酸和S 8合成二苯并噻吩。
Selective Palladium-Catalysedipso Arylation of α,α-Disubstituted Benzo[b]thien-2-ylmethanols with Aryl Bromides using PCy3 as Ligand
作者:A. Beatrix Bíró、András Kotschy
DOI:10.1002/ejoc.200600929
日期:2007.3
α,α-Diphenylbenzo[b]thien-2-ylmethanol was treated with a series of arylbromides in the presence of palladium(II) acetate and tricyclohexylphosphane to give the appropriate 2-aryl-benzo[b]thiophenes in good to excellent yield with concomitant formation of benzophenone. The reaction wassuccessfully extended to α,α-diphenylbenzo[b]thien-3-ylmethanol, although in certain cases the transformation was