THE PREFERENTIAL TOSYLATION OF THE ENDO-5-HYDROXYL GROUP OF 1,4;3,6-DIANHYDRO-D-GLUCITOL

Abstract

Reaction of 1,4;3,6-dianhydro-D-glucitol (isosorbide) with an equimolar amount of tosyl chloride in pyridine gave a fourfold greater yield of the endo-5-tosylate (IV) than of the exo-2-tosylate (III). Compound III reacted about 1.4 times more rapidly with tosyl chloride than did IV. The structures of III and IV were established by infrared spectroscopy and by their reaction with sodium methoxide. The exo-tosyloxy group of the monoacetate of III resists replacement by iodide ion.