Electrochemical Sulfonylation of Electron-Rich Aromatic Substrates with Sodium Sulfinates

Abstract

The use of electricity in organic synthesis is characterized by various advantages over conventional methods in terms of reaction selectivity, safety, and sustainability.[1] The use of electrons as reagents, as well as precise reaction control, allows direct C–H bond activation, resulting in less reagent waste. The combination of supporting electrolyte and coupling component, therefore, has a particularly positive effect on the atomic efficiency. Regarding this, we present an electrochemically driven synthesis of various aryl and diaryl sulfones,[2] which amongst others are an important structural motif in pharmaceutical active ingredients.[3] This electrochemical protocol, based on boron-doped diamond electrodes (BDD) and 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP) as solvent, leads to a direct C–S coupling of electron-rich aromatic substrates with sodium sulfinates. The last ones are used combinatorially as supporting electrolytes and coupling components, which makes this method a sustainable contribution to the organic synthesis of sulfones.