Efficient Assembly of Chromone Skeleton from 2,3-Allenoic Acids and Benzynes
作者:Guobi Chai、Youai Qiu、Chunling Fu、Shengming Ma
DOI:10.1021/ol202076c
日期:2011.10.7
Chromone derivatives were synthesized from 2,3-allenoicacids and benzynes in moderate to excellent yields under mild conditions. Instead of the cyclic conjugate addition of the intermediate A formed by the nucleophilic addition of allenoic acid with benzyne, this intermediate undergoes 1,2-addition with the carbonyl group, which was followed by the ring opening, conjugate addition, and protonolysis