Catalytic Lewis acid phosphorylation with pyrophosphates

We report a method for the Lewis acid catalyzed phosphorylation of alcohols with pyrophosphates. Ti(O^tBu)₄ was found to be the most effective catalyst in the phosphorylation of both primary and secondary alcohols with tetrabenzylpyrophosphate, providing conversions between 54% and >98% and isolated yields between 50% and 97%. Other pyrophosphates with orthogonal protecting groups were synthesized and screened to validate the generality of the approach. This study will describe how benzyl, methyl, ethyl, allyl, and o-nitrobenzyl pyrophosphates are all effective phosphorylating agents under Lewis acid catalysis.