Improved Chemistry of myo-Inositol: A New Synthetic Strategy to Protected 1-Keto- and 1,2-Keto-Inososes

A refresh and improvement of the well-known myo-inositol chemistry is reported here, setting up a new synthetic protocol to obtain orthogonally protected compounds, with a special focus on the preparation of 2-O-alkylated compounds. A gram scale synthesis of the 2-allyl compound was performed and optimized in terms of yield. This intermediate is the precursor of chiro-1-inosose, for which synthetic procedures are lacking. Taking advantage of the easily handled allyl group, we were able to transform this keto compound into both the 1,2-diketone and 3-deoxy-1,2-diketone, intermediates of biological transformations used in several patented applications. Finally, to access poly-hydroxylated-(aminomethyl)cyclohexane compounds, the reaction of the keto compound with cyanide was optimized, affording cyanohydrins obtained as single stereoisomer, the precursor of the above compound.