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Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
Electrochemical Cross-Dehydrogenative Coupling of Isochroman and Unactivated Ketones
Huan Cao1, Chao-Jiu Long1, Dan Yang1
1Key Laboratory of Applied Chemistry of Chongqing Municipality, School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.
Abstract:
An unprecedented electrochemical cross-dehydrogenative coupling reaction between isochroman and unactivated ketones to directly synthesize α-substituted isochromans has been developed. This strategy provides a facile and efficient procedure to the direct activation of C(sp3)-H bond adjacent to the O atom of isochroman. The method features high atom economy, chemical oxidant-free, and mild conditions, in which methanesulfonic acid (MsOH) acts as both electrolyte and catalyst, making the process more convenient and environmentally friendly. Gram-scale experiment and synthesis of antitumor active compounds demonstrate the great potential of this protocol for practical applications.
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