α-Methoxyketone Synthesis via Ketone Homologation: ZrCl4- Mediated Hydroxy Sulfone Rearrangements.

The adducts between ketones and the anion derived from [(methoxymethyl)sulfonyl]benzene undergo efficient, regioselective rearrangement to give α-methoxyketones when treated with ZrCl4 and HfCl4; this new procedure allows the sulfone-mediated homologation methodology to be applied to monocyclic and acyclic ketones.