Single-Flask Multicomponent Palladium-Catalyzed α,γ-Coupling of Ketone Enolates: Facile Preparation of Complex Carbon Scaffolds
Michael Grigalunas1, Per-Ola Norrby1,2, Olaf Wiest1,3
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (USA).
Abstract:
A three-component palladium-catalyzed reaction sequence has been developed in which γ-substituted α,β-unsaturated products are obtained in a single flask by an α-alkenylation with either a subsequent γ-alkenylation or γ-arylation of a ketone enolate. Coupling of a variety of electronically and structurally different components was achieved in the presence of a Pd/Q-Phos catalyst (2 mol %), usually at 22 °C with yields of up to 85 %. Most importantly, access to these products is obtained in one simple operation in place of employing multiple reactions.
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