Synthesis of Trisubstituted Isoxazoles by Palladium(II)-Catalyzed Cascade Cyclization–Alkenylation of 2-Alkyn-1-one <i>O</i>-Methyl Oximes
作者:Zhigang She、Dongyue Niu、Lei Chen、Maria A. Gunawan、Xhesika Shanja、William H. Hersh、Yu Chen
DOI:10.1021/jo300090k
日期:2012.4.6
palladium-catalyzed, cascade 5-endo-dig cyclization–alkenylation synthesis of isoxazoles has been developed. The addition of 1 equiv of n-Bu4NBr significantly increases the yield of the desired 4-alkenyl-3,4,5-trisubstituted isoxazoles. A variety of trisubstitutedisoxazoles are prepared in moderate to excellent yields. One example of the synthesis of a naphthoisoxazole is reported by a cascade cyclization–alkenylation-Heck