Scalable, Chemoselective Nickel Electrocatalytic Sulfinylation of Aryl Halides with SO₂

Abstract

Simple access to aryl sulfinates from aryl iodides and bromides is reported using an inexpensive Ni‐electrocatalytic protocol. The reaction exhibits a broad scope, uses stock solution of simple SO2 as sulfur source, and can be scaled up in batch and recycle flow settings. The limitations of this reaction are clearly shown and put into context by benchmarking with state‐of‐the‐art Pd‐based methods.

EnT-Mediated N–S Bond Homolysis of a Bifunctional Reagent Leading to Aliphatic Sulfonyl Fluorides

“…However, direct introduction of the sulfonyl fluoride click motif largely remained dependent on a few selected sulfonyl fluoride hubs as well as halide exchange reactions until the early 2010s, significantly constricting the choice of SuFEx coupling subjects. Assessing the challenges bounded with a versatile installation of the SO 2 F motif, metal-catalyzed , and electrochemical , strategies have been developed to synthesize primarily unsaturated sulfonyl fluorides.…”

A guide to organic electroreduction using sacrificial anodes

“…Very recently, the Baran group reported a Ni-catalyzed sulfinylation of aryl halides using SO 2 as the sulfur source (Scheme 15). 39 To facilitate isolation of the sulfinylated products, sulfinates 76 were in situ transformed to sulfonyl fluorides 77 . The lower reduction potential of the in situ released Zn ions could prevent the formation of undesired proto-dehalogenation.…”

Electrochemical sulfinylation of phenols with sulfides: a metal- and oxidant-free cross-coupling for the synthesis of aromatic sulfoxides

“…4 In addition, these sulfinates (existing in the S IV -oxidation state) are well-established and reliable precursors or intermediates to diverse structurally and biologically significant functionalities existing in either the S IV or S VI oxidation states such as sulfones, sulfoximine, sulfinamides, sulfonate esters, sulfinate esters, sulfonyl halides, and others. 5 In spite of their tremendous importance, there are only a few trivial strategies disclosed so far to construct aromatic sulfoxides. Although the direct mono-oxidation of diaryl sulfides has been a straightforward approach, 6 the palladium-catalyzed cross-coupling of sulfenate anions by Poli and Madec, 7 Walsh, 8 Nolan, 9 and Perrio 10 has emerged as a promising gateway to these aryl sulfoxides.…”

“…4 In addition, these sulfinates (existing in the S IV -oxidation state) are well-established and reliable precursors or intermediates to diverse structurally and biologically significant functionalities existing in either the S IV or S VI oxidation states such as sulfones, sulfoximine, sulfinamides, sulfonate esters, sulfinate esters, sulfonyl halides, and others. 5…”