Visible Light Photocatalytic Reduction of O-Thiocarbamates: Development of a Tin-Free Barton-McCombie Deoxygenation Reaction

• Published in: Advanced synthesis & catalysis Vol. 356; no. 13; pp. 2756 - 2762
• Main Authors: Chenneberg, Ludwig, Baralle, Alexandre, Daniel, Marion, Fensterbank, Louis, Goddard, Jean-Philippe, Ollivier, Cyril
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 15.09.2014; WILEY‐VCH Verlag; Wiley; Wiley-VCH Verlag
• Subjects: Activation analysis; Chemical Sciences; Chemistry; Chemistry, Applied; Chemistry, Organic; Chemists; Deoxygenation; Organic chemistry; Photocatalysis; photoreduction; Physical Sciences; Precursors; Quenching; radical reactions; Science & Technology; thiocarbamates; Transformations; RADICAL DEOXYGENATION; thiocarbamates; DIAZONIUM SALTS; ALKYL; SULFONIUM SALTS; radical reactions; PHOTOREDOX CATALYSIS; deoxygenation; FUNCTIONALIZATION; photoreduction; TERTIARY ALCOHOLS; PSCHORR REACTION; photocatalysis; BOND; DERIVATIVES
• ISSN: 1615-4150; 1615-4169
• DOI: 10.1002/adsc.201400729

The Barton–McCombie deoxygenation is one of the most important transformations in the toolbox of organic chemists which has been the subject of a number of methodological developments. In this study, we report a photocatalyzed redox deoxygenation of secondary and tertiary alcohols from thiocarbamate precursors under visible light activation. The iridium complex Ir(ppy)3 proved to be the most efficient catalyst in the presence of Hünig’s base as sacrifial electron donor. A mechanistic investigation is presented based on fluorescence quenching experiments and cyclic voltammetry.