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Asymmetric Ni-catalyzed conjugate allylation of activated enones.

ABSTRACT: The nickel-catalyzed enantioselective addition of allylboronic acid pinacol ester, allylB(pin), is described. This reaction is highly effective with dialkylidene ketones and favors the allylation of the benzylidene site in nonsymmetric substrates. The reaction appears to proceed by conversion of the dialkylidene ketone substrate to an unsaturated pi-allyl complex (I), followed by reductive elimination. Enantioselectivities range from 91 to 94% ee for a range of substrates when chiral ligand 14 is employed.

SUBMITTER: Sieber JD

PROVIDER: S-EPMC3065355 | biostudies-literature | 2008 Apr

REPOSITORIES: biostudies-literature

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Asymmetric Ni-catalyzed conjugate allylation of activated enones.

Sieber Joshua D JD Morken James P JP

Journal of the American Chemical Society 20080314 14

The nickel-catalyzed enantioselective addition of allylboronic acid pinacol ester, allylB(pin), is described. This reaction is highly effective with dialkylidene ketones and favors the allylation of the benzylidene site in nonsymmetric substrates. The reaction appears to proceed by conversion of the dialkylidene ketone substrate to an unsaturated pi-allyl complex (I), followed by reductive elimination. Enantioselectivities range from 91 to 94% ee for a range of substrates when chiral ligand 14 i ...[more]

PMID: 18338891

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