摘要:
Starting from alpha-allyloxy esters, divinyl carbinols with diastereotopic vinyl groups become accessible. Diastereoselectivity for ring closing metathesis reactions of these trienes was investigated. Formation of a spirocyclic derivative proceeds with significant diastereoselectivity, and a mechanistic proposal for the diastereoselective formation of spirocyclic derivatives is presented. (C) 2000 Elsevier Science Ltd. All rights reserved.