Efficient Preparation of β-Branched γ,δ-Unsaturated Esters through Copper-Catalyzed Allylic Alkylation of Ketene Silyl Acetal

Abstract

Copper-catalyzed allylic alkylation of ketene silyl acetals proceeded with excellent γ-E-selectivity. Efficient α-to-γ chirality transfer with anti-selectivity occurred in the reaction of enantioenriched secondary allylic phosphates, affording enantioenriched β-branched γ,δ-unsaturated esters. The reaction was readily scalable and highly reliable in terms of product yield and stereoselectivities.

γ,δ-unsaturated esters - copper - allylic alkylation - ketene silyl acetal - regioselectivity

References

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See the Supporting Information of ref. 6 for procedures

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