Acetalation studies. Part VII. Some new aspects of the isopropylidenation of galactitol

Reaction of galactitol in dimethyl sulphoxide, with 2,2,-dimethoxypropane-pyridinium p-toluenesulphonate has led to the isolation of some new isopropylidene acetals. Their structures have been established spectroscopically. Attempts have been made to assess their possible role in the conventional acid-catalysed isopropylidenation of this hexitol.