The Mitsunobu reaction of ortho-ethers of secondary benzylic alcohols. Concise enantioselective synthesis of a key intermediate of the novel beta-adrenergic receptor antagonist MY336-a

Chiral secondary benzylic alcohols bearing an ortho-alkoxy substituent suffer ring-assisted racemization during the Mitsunobu reaction; however, their congeners bearing also a 3-substituent undergo virtually complete Mitsunobu inversion. A concise enantioselective synthesis of a key intermediate of the beta-adrenergic receptor antagonist MY336-a was achieved exploiting this observation. Copyright (C) 1996 Elsevier Science Ltd