Hydride Shift Generated Oxonium Ions:Evidence for Mechanism and Intramolecular Trapping Experiments to Form trans THF Derivatives

摘要

Given the large number and variety of tetrahydrofuran (THF) rings in natural products (many with interesting and useful biological activity),we are engaged in the development of new methods to prepare these heterocycles with control of all aspects of stereo- and regiochemistry.In this regard,we have recently reported a general method for the catalytic oxidative cyclization of vicinal alcohols,and derivatives thereof,onto proximal alkenes,thus forming cis-2,5-disubstituted THF rings (Scheme 1).