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Updated: Dec 24, 2025
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Control of Absolute Stereochemistry in Transition-Metal-Catalysed Hydrogen-Borrowing Reactions
Timothy Kwok1, Oskar Hoff1, Roly J Armstrong1
1Chemistry Research Laboratory, University of Oxford, Oxford, OX1 3TA, UK.
Abstract:
Hydrogen-borrowing catalysis represents a powerful method for the alkylation of amine or enolate nucleophiles with non-activated alcohols. This approach relies upon a catalyst that can mediate a strategic series of redox events, enabling the formation of C-C and C-N bonds and producing water as the sole by-product. In the majority of cases these reactions have been employed to target achiral or racemic products. In contrast, the focus of this Minireview is upon hydrogen-borrowing-catalysed reactions in which the absolute stereochemical outcome of the process can be controlled. Asymmetric hydrogen-borrowing catalysis is rapidly emerging as a powerful approach for the synthesis of enantioenriched amine and carbonyl containing products and examples involving both C-N and C-C bond formation are presented. A variety of different approaches are discussed including use of chiral auxiliaries, asymmetric catalysis and enantiospecific processes.
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