Dioxolane-to-Bridged Acetal-to-Spiroketal via Ring-Closing Metathesis and Rearrangement: A Novel Route to 1,7- Dioxaspiro[5.5]undecanes
作者:Valerie A. Keller、Joseph R. Martinelli、Eric R. Strieter、Steven D. Burke
DOI:10.1021/ol0172368
日期:2002.2.1
Several examples of 1,7-dioxaspiro[5.5]undecane spiroketal systems have been synthesized from the common bicyclic intermediate 1 via acid-catalyzed rearrangement. Intermolecular ketalization of C(2) symmetric diene diol 3 with ketone 9 and then desymmetrization by ring-closing metathesis rapidly constructs bicyclic acetal 1. The locked conformation and steric bias of 1 allow stereoselective functionalization