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Updated: May 29, 2025
A Microwave-Assisted Direct Heteroarylation of Ketones Using Transition Metal Catalysis
Published on: February 16, 2020
Dynamic Kinetic Resolution Allows Control of Remote Stereochemistry in Asymmetric Hydrogen Borrowing Alkylation
Daniella M J Cheang1, Jessica L Crompton1, Mostafa M Amer1
1Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA (UK).
Abstract:
A catalytic asymmetric method for the synthesis of γ-substituted ketones via hydrogen borrowing alkylation of both racemic linear precursors and 1,5-diols is described. The base mediated racemization of an intermediate cyclohexenone to facilitates a dynamic kinetic resolution, affording highly enantioenriched cyclohexanes in excellent yields, which could be further functionalized by removal of the Ph* group. DFT modelling revealed the mode of enantioinduction to be a stepwise process comprising of a hydride transfer and a coordination change to a π-allylic enolate complex with the iridium catalyst.
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