Organocatalytic Asymmetric Conjugate Addition and Cascade Acyl Transfer Reaction of α-Nitroketones
作者:Rui-jiong Lu、Yun-yun Yan、Jin-jia Wang、Quan-sheng Du、Shao-zhen Nie、Ming Yan
DOI:10.1021/jo2009752
日期:2011.8.5
Organocatalytic asymmetric conjugate addition of α-nitroketones to β,γ-unsaturated α-keto esters has been developed. A pyrrolidine-based thiourea–tertiary amine was identified as the best catalyst. The reaction was found to proceed via cascade conjugate addition and acyl transfer reaction. A number of α-nitroketones and β,γ-unsaturated α-keto esters were examined in this transformation. 5-Nitro-2-
已经开发了将有机生物催化不对称的α-硝基酮共轭加成到β,γ-不饱和的α-酮酯上。吡咯烷基硫脲叔胺被认为是最好的催化剂。发现该反应通过级联共轭物加成和酰基转移反应进行。在该转化中检查了许多α-硝基酮和β,γ-不饱和α-酮酯。以良好的收率(高达99%)和对映选择性(高达99%ee)获得了5-硝基-2-酰氧基戊-2-烯酸酯。可以将产物水解以提供5-硝基-2-氧戊酸,这不能通过将硝基甲烷直接添加到β,γ-不饱和的α-酮酯中获得。