A Concise Formal Total Synthesis of (+/-)-Centrolobine via DDQ-Mediated Diastereoselective Allylation and Ring-Closing Metathesis

摘要

An expedient approach to the construction of arylated 2,6-cis-disubstituted dihydropyran framework was developed involving subsequent DDQ-mediated diastereoselective allylation at an oxygen-substituted benzylic position and ring-closing metathesis (RCM) as key transformations. The synthetic utility of the methodology was illustrated by a formal total synthesis of (+/-)-centrolobine in five steps from the known homoallylic alcohol or in eight steps from the readily available THP-protected glycidol. This route allows for direct access towards other diarylheptanoid natural products and their synthetic analogues with a variety of side chains.