Thioetherification via Photoredox/Nickel Dual Catalysis

• Published in: Organic letters Vol. 18; no. 4; pp. 876 - 879
• Main Authors: Jouffroy, Matthieu, Kelly, Christopher B, Molander, Gary A
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 19.02.2016; Amer Chemical Soc
• Subjects: Catalysis; Chemistry; Chemistry, Organic; Esterification; Hydrocarbons, Brominated - chemistry; Letter; Molecular Structure; Nickel - chemistry; Oxidation-Reduction; Physical Sciences; Science & Technology; Silicates - chemistry; Sulfides - chemistry; ORGANIC-SYNTHESIS; GOLD; BOND-DISSOCIATION ENERGIES; MERGING PHOTOREDOX; TRANSITION-METAL-COMPLEXES; NICKEL CATALYSIS; VISIBLE-LIGHT PHOTOREDOX; ARYL HALIDES; THIYL RADICALS; SINGLE-ELECTRON TRANSMETALATION
• ISSN: 1523-7060; 1523-7052
• DOI: 10.1021/acs.orglett.6b00208

Hypervalent alkylsilicates represent new and readily accessible precursors for the generation of alkyl radicals under photoredox conditions. Alkyl radicals generated from such silicates serve as effective hydrogen atom abstractors from thiols, furnishing thiyl radicals. The reactive sulfur species generated in this manner can be funneled into a nickel-mediated cross-coupling cycle employing aromatic bromides to furnish thioethers. The serendipitous discovery of this reaction and its utilization for the thioetherification of various aryl and heteroaryl bromides with a diverse array of thiols is described. The S–H selective H atom abstraction event enables a wide range of functional groups, including those bearing protic moieties, to be tolerated.