Simple and efficient routes to optically active chiro- and allo-inositol derivatives from myo-inositol

Efficient routes for the gram scale syntheses of optically active chiro- and allo-inositol derivatives from readily available 1,2:4,5-di-O-isopropylidene-myo-inositol (1) are described. Both D and L forms of these isomeric inositols could be synthesized from enantiomers of 1. One-pot methodology for the simultaneous synthesis of both chiro and allo has also been developed. The possible selectivity for the cleavage of trans-ketal in presence of the cis is an added advantage for the syntheses of a variety of protected derivatives for phosphoinositol syntheses. These routes provide synthetically flexible 1,2:4,5-di-O-isopropylidene-chiro-inositol and 1,6:3,4-di-O-isopropylidene-allo-inositol which are difficult to achieve otherwise.