Facile selective cleavage of a myo-inositol trans-isopropylidene acetal in the presence of a cis-isopropylidene acetal

1,2:4,5-Di-O-isopropylidene myo-inositol acetals were selectively deprotected at the 4,5-trans position using Amberlite-120 (H+) resin in CHCl3/MeOH at room temperature over 24–48 h to afford the corresponding cis-1,2-O-isopropylidene myo-inositol acetals in near quantitative yield.