Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Org Lett. 2011 Sep 16;13(18):4870-2. doi: 10.1021/ol201949h. Epub 2011 Aug 18.
Synthetically useful rhodium(II) carbenes were obtained from N-(1,2,4-triazolyl)-substituted 1,2,3-triazoles and Rh(II) carboxylates. The electron-withdrawing 1,2,4-triazolyl group reveals the heretofore unknown reactivity of nonsulfonyl 1,2,3-triazoles, which exhibit the reactivity of diazo compounds. The resulting carbenes provide ready asymmetric access to secondary homoaminocyclopropanes (80-95% ee, dr >20:1) via reactions with olefins and also engage in efficient transannulation reactions with nitriles.
合成上有用的铑(II)卡宾是从 N-(1,2,4-三唑基)取代的 1,2,3-三唑和 Rh(II)羧酸盐中获得的。吸电子的 1,2,4-三唑基揭示了以前未知的非砜基 1,2,3-三唑的反应性,其表现出重氮化合物的反应性。得到的卡宾通过与烯烃的反应提供了易于获得的手性仲同环丙胺(80-95%ee,dr>20:1)的不对称途径,并且还与腈进行有效的交叉环化反应。