Synthesis of benzil-o-carboxylate derivatives and isocoumarins through neighboring ester-participating bromocyclizations of o-alkynylbenzoates
作者:Si-Tian Yuan、Hongwei Zhou、Lianpeng Zhang、Jin-Biao Liu、Guanyinsheng Qiu
DOI:10.1039/c7ob00845g
日期:——
A bromide salt mediated neighboring ester-participated bromocyclization of o-alkynylbenzoates is described here for synthesis of benzil-o-carboxylate. 4-bromoisocoumarins are also reached when phenyl o-alkynylbenzoate is used as the substrate. Mechanism studies suggest that the whole process is comprised by electrophilic bromocyclization and dibromohydration-based ring-opening, and the neighboring
此处描述了溴盐介导的邻炔基苯甲酸酯的邻酯参与的溴环化,以合成苄基邻羧酸酯。当苯基邻炔基苯甲酸苯酯用作底物时,也能达到4-溴异香豆素。机理研究表明,整个过程由亲电溴环化和基于二溴水合的开环组成,并且相邻的酯基参与溴环化。有趣的是,邻苯甲酸苄酯中的酮羰基的两个氧原子均来自水。亲电性溴源是由溴化物盐的氧化原位产生的。