Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States.
Org Lett. 2011 May 6;13(9):2388-91. doi: 10.1021/ol2006242. Epub 2011 Apr 12.
A Cu-catalyzed method for coupling 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 Cu 催化的方法，用于将α-取代的-α-重氮酯与末端炔烃偶联，得到取代的烯丙酸盐。选择性方法的关键是认识到一种偶然的碱催化异构化形成烯丙酸盐产物。基于部分证据反对涉及 Cu(I)-炔化物作为低价中间体的机理，提出了一个合理的机理。
