Patent ID: 8921585

Claim:
A method for synthesizing dianhydrogalactitol (DAG) using dulcitol as a starting material comprising the steps of: (a) reacting dulcitol with hydrobromic acid (HBr), carbon tetrabromide (CBr 4 ) and triphenylphosphine (Ph 3 P), para-toluenesulfonyl chloride (tosyl chloride), or trifluoromethanesulfonic anhydride (triflic anhydride) to convert the 1,6-hydroxy groups of dulcitol to 1,6-dibromo, 1,6-ditosylate, or 1,6-ditriflate groups, which provides 1,6-dibromodulcitol, 1,6-ditosyldulcitol or 1,6-ditriflatedulcitol; and (b) reacting the 1,6-dibromodulcitol, 1,6-ditosyldulcitol, or 1,6-ditriflatedulcitol with an inorganic weak base to produce DAG through an intramolecular S N 2 reaction.