Concerning the reactivities of the C-1, C-2 and C-6 hydroxy groups of myo-inositol

Regioselectivities in the reactions of the three contiguous free hydroxy gr oups at C-6, C-1, and C-2 of 3,4,5-tri- O-benzyl-D-myo -inositol have been examined. Stannylene activation permits selective alkylation and esterifica tion at C-1; however, acyl migration back and forth between C-1 and C-2 lea ds to unpredictable ratios of the isolated regioisomers. With the stable C1 -alkylated products, further alkylation is regioslective for the axial C-2- OH, whereas acylation is regioselective for the equatorial C-6-OH. In most cases the 'other' regioisomer is not observed, the by-products being those of dialkylation or diacylation.