Acid-Controlled Access to β‑Sulfenyl Ketones and α,β-Disulfonyl Ketones by Pummerer Reaction of β‑Keto Sulfones and Sulfoxides

A convenient acid-mediated reaction of β-keto sulfones
with
sulfoxides under metal-free conditions has been developed, thereby
delivering the acid-controlled synthesis of β-sulfenyl ketones
and α,β-disulfonyl ketones in good to excellent yields.
The mechanism of the transformations has been studied carefully, which
suggested the involvement of a radical process in the formation of
α,β-disulfonyl ketones.