Highly stereoselective synthesis of C-vinyl furanosides through acid-catalyzed SN2 inversion at the C-3 position of 1,2-dideoxy-hept-1-enitols

A highly stereoselective synthesis of C-vinyl furanosides through the SN2 inversion at the C-3 position of the 1,2-dideoxy-hept-1-enitols is disclosed. Treatment of the 1,2-dideoxy-hept-1-enitols with diphenylammonium trifluoromethanesulfonate as the acid catalyst produced the C-vinyl furanosides (3,6-anhydro-1,2-dideoxy-hept-1-enitol derivatives) via a subsequent SN2 intramolecular debenzyloxyation–cycloetherification reaction at the C-3 position.