Tandem Cross-Dimerisation/Oxonia-Cope Reaction of Carbonyl Compounds to Homoallylic Esters and Lactones

摘要

Homoallylic subunits constitute ubiquitous structural motifs in organic chemistry, and their stereoselective introduction is of fundamental academic and industrial importance. In addition to carbonyl ene reactions, allylations of carbonyl compounds with allylic organometal species represent the main route to these subunits. The reactivity of diverse reagents can be tuned to effect high levels of diastereo- and enantioselectivity, which usually originates from the chairlike 6-membered-ring transition state A (Scheme l).