Highly Chemoselective Reduction of Amides (Primary, Secondary, Tertiary) to Alcohols using SmI<sub>2</sub>/Amine/H<sub>2</sub>O under Mild Conditions
作者:Michal Szostak、Malcolm Spain、Andrew J. Eberhart、David J. Procter
DOI:10.1021/ja412578t
日期:2014.2.12
Highly chemoselective direct reduction of primary, secondary, and tertiary amides to alcohols using SmI2/amine/H2O is reported. The reaction proceeds with C–N bond cleavage in the carbinolamine intermediate, shows excellent functional group tolerance, and delivers the alcohol products in very high yields. The expected C–O cleavage products are not formed under the reaction conditions. The observed
据报道,使用 SmI2/胺/H2O 将伯、仲和叔酰胺高度化学选择性地直接还原为醇。该反应在甲醇胺中间体中进行 C-N 键断裂,显示出优异的官能团耐受性,并以非常高的产率提供醇产物。在反应条件下不会形成预期的 C-O 裂解产物。观察到的反应性与由 nX → π*C=O (X = O, N) 共轭产生的极性羰基的亲电性相反。机理研究表明,在四面体中间体中,Sm 与羰基和路易斯碱性氮的配位促进了电子转移并控制了 C-N/C-O 裂解的选择性。尤其,