Stereoselective Dearomatizing Addition of Nucleophiles to Uncomplexed Benzene Rings: A Route to Carbocyclic Sugar Analogues

Abstract

Versatile synthetic intermediates were formed by the dearomatization of 2-aryl 4,5-diphenyloxazolines with secondary alkyl lithium reagents in the presence of N,N′-dimethylpropyleneurea (DMPU; see scheme). The resulting cyclohexadiene derivatives were converted into carbocyclic analogues of mannose and altrose in a short sequence without the use of protecting groups.