Glycosylmanganese pentacarbonyl complexes: an organomanganese-based approach to the synthesis of C-glycosyl derivatives

Preparation, structure and reactions of glycosylmanganese pentacarbonyl com plexes are discussed. Anomerically pure complexes of pyranosyl and furanosy l complexes were prepared in excellent yield. The conformations of the anom eric glucosyl and mannosyl complexes were derived from detailed analysis of their 1D and 2D H-1- and C-13-NMR spectra including NOE data. The complexe s are further characterized by Mn-55-NMR chemical shifts and Mn-55, C-13 on e-bond coupling constants. These compounds undergo various migratory insert ion reactions resulting in formation of C-glycosyl derivatives. Application s of this technology to the synthesis of C-glycosyl and C-aryl glycosidic s ystems are discussed. (C) 2000 Elsevier Science S.A. All rights reserved.