Copper-Catalyzed Synthesis of 2,4-Disubstituted Allenoates from α-Diazoesters
作者:Matthew Hassink、Xiaozhong Liu、Joseph M. Fox
DOI:10.1021/ol2006242
日期:2011.5.6
α-substituted-α-diazoesters with terminal alkynes to give substituted allenoates is described. Key to the development of a selective method was the recognition that an adventitous base catalyzes the isomerization to form the allenoate product. A plausible mechanism is proposed, based in part on evidence against a mechanism that involves a Cu(I)-acetylide as a low-valent intermediate.
描述了一种用于将 α-取代-α-重氮酯与末端炔烃偶联以产生取代的烯丙酸酯的 Cu 催化方法。开发选择性方法的关键是认识到外来碱催化异构化形成烯丙酸酯产物。提出了一种合理的机制,部分基于反对将 Cu(I)-乙炔化物作为低价中间体的机制的证据。
Blue light induced [2,3]-sigmatropic rearrangement reactions of tosylhydrazones
Metal-free blue light-mediated [2,3]-sigmatropic rearrangement reactions of tosylhydrazones and sulfides are reported herein. This strategy shows great enhancement compared to the traditional methods because of stable starting materials and mild reaction conditions. In this report, we have developed the Doyle-Kirmse reaction and Sommelet-Hauser reaction with simple operation, high yields and broad