Unexpected exo selectivity for an intramolecular Diels–Alder reaction involving a doubly-activated δ-pentenolide dienophile
摘要:
The intramolecular Diels-Alder cyclization of a homochiral doubly-activated delta-pentenolide system is described, proceeding predominantly via an exo transition state to provide an advanced precursor toward unique stereochemical analogs of (+)-symbioimine. (C) 2011 Elsevier Ltd. All rights reserved.