Direct Intramolecular Conjugate Addition of Simple Alkenes to α,β-Unsaturated Carbonyls Catalyzed by Cu(OTf)<sub>2</sub>
作者:Yan Qin、Jian Lv、Sanzhong Luo、Jin-Pei Cheng
DOI:10.1021/ol502373u
日期:2014.10.3
An unprecedented intramolecular conjugate addition of simple alkenes to α,β-unsaturated carbonyl compounds has been developed. A simple Lewis acid such as Cu(OTf)2 was found to effectively catalyze the reaction, and six- and five-membered cyclic products were obtained in moderate to high yields.
Several examples of thermallyinduced intramolecular oxy-ene reactions leading to six- or five-membered rings are reported. The yields vary from poor to good, depending on the thermal lability of the substrate. Considering the high temperatures required to effect these transformations (several hours at ca. 250°), the observed diastereoselectivities favoring the trans-1,2-substituted cycloalkane derivatives