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Optically pure 2-(l-hydroxybenzyl)piperidine and pyrrolidine were prepared by reaction of oxygenated 2-(p-tolylsulfinyl)benzyl carbanions with the appropriate chlorinated N-sulfinylimines followed by subsequent elimination of the sulfinyl groups. The main reaction is a tandem process involving nucleophilic addition of the sulfinylbenzyl carbanion to the C=N bond followed by intramolecular elimination of the chlorine by the resulting amide. The matched pair of the reagents (exhibiting the same configuration at their respective sulfinyl moieties) evolves with a complete control of the stereoselectivity at the two newly created chiral carbons.

The intramolecular glycosylation of thiomannoside donors linked through C6' by a phthaloyl group to C3 of a diol mannoside acceptor is described. The unexpected results led us to undertake a systematic analysis of the factors affecting the regioselectivity of the intermolecular process. The substituents on the diol mannoside acceptor have been found to play an important role.

A straightforward synthesis of L-chiro-inositol, deoxy L-chiro-inositol derivatives and L-chiro-inositol building blocks for the preparation of inositolphosphoglycans, is reported from myo-inositol. Glycosylation with 2-azido-3,4,6-tri-O-benzyl-2-deoxy-D-glucopyranosyl trichloroacetimidate gave the corresponding pseudodisaccharide derivatives.