Intramolecular cationic cyclization of acetoxy derivatives of the levoglucosenone-cyclopentadiene endo-adduct

Abstract

Epoxidation of diastereoisomeric benzyloxy derivatives of the levoglucosenone adduct with cyclopentadiene by treatment with m-chloroperoxybenzoic acid afforded a mixture of 1,2- and 1,4-epoxy derivatives. Intramolecular cyclization of the hydroxy derivatives of the same adduct by the action of I2-NaHCO3-MeCN gave products resulting from cleavage of the 1,6-anhydro bridge, reduction of the acetal moiety, and olefinaldehyde cyclization.