Alternative syntheses of 1-, 2-, and 3-O-methyl-D-mannitol

1-O-Methyl-D-mannitol has been prepared by treating 1,2-anhydro-3,4:5,6-di-O-isopropylidene-D-mannitol with sodium methoxide. 2-O-Methyl-D-mannitol has been obtained by stepwise hydrolysis of 1,2,6-tri-O-benzoyl-3,4-O-isopropylidene-D-mannitol, and 3-O-methyl-D-mannitol has been isolated after reduction of 3-O-methyl-D-fructose with Raney nickel.