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Updated: Jun 20, 2025

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
Photoredox-Neutral Radical-Radical Cross-Coupling of Isatins and Benzyl Carboxylic Acids
Chun-Lin Dong1, Han-Chi Liu1, Zhi Guan1
1Key Laboratory of Applied Chemistry of Chongqing Municipality, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
Abstract:
A photoredox-neutral radical-radical cross-coupling is described for the synthesis of 3-hydroxy-3-alkyloxindoles using isatins and benzyl carboxylic acids as substrates and 2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) as the photocatalyst. The method features a broad substrate scope and good functional group tolerance, providing 30 sterically hindered alcohols with moderate to excellent yields. This approach utilizes inexpensive and commercially available starting materials, avoiding the use of transition metals, extra oxidants/reductants, and harsh reaction conditions, showcasing significant applicability and environmental friendliness.
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