Sulfonylation of Bismuth Reagents with Sulfinates or SO₂ through Bi^III/Bi^V Intermediates

Studies to explore the catalytic activities of main-group elements are attractive. We report here our study of sulfonylation of bismuth reagents with sulfinates or SO₂ surrogates. Under oxidative conditions, triarylbismuthines and sulfinates were transformed into diaryl sulfones. A transition-metal-like two-electron redox process at the Bi center was achieved in this reaction. Sulfur dioxide generated in situ can also replace sulfinates to deliver the corresponding symmetric diaryl sulfones. A rational mechanism for this reaction was also proposed that involves a Bi­(III)–Bi­(V) manifold.