Asymmetric Lewis Acid-Catalyzed Diels−Alder Reactions of α,β-Unsaturated Ketones and α,β-Unsaturated Acid Chlorides
作者:Joel M. Hawkins、Mitch Nambu、Stefan Loren
DOI:10.1021/ol035524t
日期:2003.11.1
[reaction: see text] Conformational analysis, van der Waals attractions, and transition structure calculations are combined to design an asymmetric Lewis acid-catalyzed Diels-Alder reaction for simple acyclic alpha,beta-unsaturated ketones and alpha,beta-unsaturated acid chlorides, giving up to 83 and 92% ee, respectively. The two-point-binding chiral recognition mechanism, Lewis acid-Lewis base coordination
[反应:请参阅文字]结合构象分析,范德华吸引力和过渡结构计算,设计了用于简单无环α,β-不饱和酮和α,β-不饱和酰氯的不对称路易斯酸催化Diels-Alder反应,分别放弃83%和92%的ee。两点结合的手性识别机理,即路易斯酸-路易斯碱与硼的配位和范萘瓦尔斯与萘基的吸引,使用简单的α,β-不饱和羰基化合物固有的烯酮单元,从而消除了对辅助氧的需求双亲物上的结合位点。