The allylation of dibutylstannylene derivatives of myo-inositol

Abstract

Reaction of myo-inositol or a mixture of racemic 1,4-, 1,6-, and 4,5-di-O-allyl-myo-inositol in acetonitrile with dibutyltin oxide and allyl bromide in the presence of tetrabutylammonium bromide gave, as the major products, a readily separable mixture of 1,3,4,6- and 1,3,4,5-tetra-O-allyl-myo-inositol together with small proportions of penta-O-allyl-myo-inositols and 1,3,5-tri-O-allyl-myo-inositol (from myo-inositol). Parallel results were obtained when crotyl bromide was used. When 3 equiv. of dibutyltin oxide were used with myo-inositol or 1 equiv. with the mixture of di-O-allyl derivatives, 1,3,4-tri-O-allyl-myo-inositol was the major product. When 2 equiv. of dibutyltin oxide were used, myo-inositol gave a complex mixture of mono-, di-, and tri-O-allyl derivatives which was fractionated after conversion into the O-isopropylidene derivatives. Racemic 1,3,4,5-tetra-O-allyl-myo-inositol was resolved via the (−)-ω-camphanates.