Iodomethyl group as a hydroxymethyl synthetic equivalent: Application to the syntheses of D-manno-hept-2-ulose and L-fructose derivatives

The one-carbon elongation of aldoses to ketoses using iodomethyllithium as the key reagent in the homologation step is exemplified by the preparation of two carbohydrates of chemical and biological interests:  d-manno-hept-2-ulose from d-mannose and l-fructose from l-arabinose.