the mechanism of the boekelheide reaction begins by an acyl transfer from the trifluoroacetic anhydride to the "n"-oxide oxygen. the α-methyl carbon is then deprotonated by the trifluoroacetate anion. this sets the molecule up for a [3.3]-sigmatropic rearrangement which furnishes the trifluoroacetylated methylpyridine. hydrolysis of the trifluoroacetate releases the hydroxymethylpyridine.