Sulfonate Protecting Groups: Synthesis of D- and L-myo-Inositol-1,3,4,5-tetrakisphosphate Precursors by a Novel Silver(I) Oxide-Mediated O-Alkylation of 2,4(6)-Di-O-acyl-6(4)-O-sulfonyl-myo-Inositol 1,3,5-Orthoformate Derivatives Through Intramolecular Assistance of the Sulfonyl Group

Abstract

Alkylation of racemic 2,4-di-O-acyl-6-O-sulfonyl-myo-inositol 1,3,5-orthoformates mediated by silver(I) oxide affords the corresponding racemic 2,4-di-O-alkyl-6-O-sulfonyl-myo-inositol 1,3,5-orthoformates in good yields. Control experiments suggest that these unusual reactions are due to intramolecular assistance by the sulfonyl group. O-Alkylation reactions of myo-inositol 1,3,5-orthoformate derivatives provide a new route for the synthesis of important ether derivatives of myo-inositol, which are intermediates for the preparation of phosphoinositols. The utility of this method is demonstrated by the preparation of D- and L-2,4-di-O-benzyl-myo-inositols, which were obtained by benzylation of 2,4-di-O-benzoyl-6-O-camphorsulfonyl-myo-inositol 1,3,5-orthoformate and 2,6-di-O-benzoyl-4-O-camphorsulfonyl-myo-inositol 1,3,5-orthoformate.