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Catalytic asymmetric ?-alkylation of carbonyl compounds via stereoconvergent Suzuki cross-couplings.

ABSTRACT: With the aid of a chiral nickel catalyst, enantioselective ?- (and ?-) alkylations of carbonyl compounds can be achieved through the coupling of ?-haloamides with alkylboranes. In addition to primary alkyl nucleophiles, for the first time for an asymmetric cross-coupling of an unactivated alkyl electrophile, an arylmetal, a boronate ester, and a secondary (cyclopropyl) alkylmetal compound are shown to couple with significant enantioselectivity. A mechanistic study indicates that cleavage of the carbon-halogen bond of the electrophile is irreversible under the conditions for asymmetric carbon-carbon bond formation.

SUBMITTER: Zultanski SL

PROVIDER: S-EPMC3183125 | biostudies-other | 2011 Oct

REPOSITORIES: biostudies-other

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Catalytic asymmetric γ-alkylation of carbonyl compounds via stereoconvergent Suzuki cross-couplings.

Zultanski Susan L SL Fu Gregory C GC

Journal of the American Chemical Society 20110913 39

With the aid of a chiral nickel catalyst, enantioselective γ- (and δ-) alkylations of carbonyl compounds can be achieved through the coupling of γ-haloamides with alkylboranes. In addition to primary alkyl nucleophiles, for the first time for an asymmetric cross-coupling of an unactivated alkyl electrophile, an arylmetal, a boronate ester, and a secondary (cyclopropyl) alkylmetal compound are shown to couple with significant enantioselectivity. A mechanistic study indicates that cleavage of the ...[more]

PMID: 21913638

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