Aminocatalytic Enantioselective 1,6 Additions of Alkyl Thiols to Cyclic Dienones: Vinylogous Iminium Ion Activation
作者:Xu Tian、Yankai Liu、Paolo Melchiorre
DOI:10.1002/anie.201202392
日期:2012.6.25
presence of chiral amines, 2,4‐dienones are activated toward the attack of a nucleophile at the δ position, a mode of activation that is termed vinylogous iminium ion catalysis. Specifically, the 1,6 addition of alkyl thiols to β‐substituted cyclic dienones was catalyzed by a cinchona‐based primary amine; the reaction was highly stereoselective and displayed high selectivity for reaction at the δ position
远程传输:在存在手性胺的情况下,2,4-二壬烯被激活,以引起亲核体在δ位的进攻,这种激活方式被称为乙烯基亚胺鎓离子催化。具体而言,基于金鸡纳胺的伯胺可催化将1,6-烷基硫醇加到β-取代的环状二烯酮上。该反应是高度立体选择性的,并且在δ位置显示出对反应的高选择性。