Stereoselective Synthesis of Substituted Tetrahydropyrans and Isochromans by Cyclization of Phenylseleno Alcohols
摘要:
A selenium-mediated strategy for the stereoselective synthesis of substituted tetrahydropyrans and isochromans has been developed starting from 5-phenylseleno ketones. After enantioselective reduction, the chiral nonracemic phenylseleno alcohols were oxidized to the conesponding selenones, which underwent an effcient 6-exo-tet ring-closure reaction.