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Catalytic enantioselective allene-anhydride approach to β,γ-unsaturated enones bearing an α-all-carbon-quarternary center.

ABSTRACT: A protocol of highly regio- and enantioselective copper-catalyzed hydroacylation of the non-terminal C[double bond, length as m-dash]C bond in 1,1-disubstituted terminal allenes with anhydrides has been developed. Both aromatic and aliphatic carboxylic anhydrides are applicable to the efficient construction of all carbon quarternary centers connected with a versatile C[double bond, length as m-dash]C bond and a useful ketone functionality. The synthetic potentials of the enantioenriched products have also been demonstrated. Density functional theory (DFT) calculations were performed to explain the steric outcome of the products: the hydroacylation proceeds through a six-membered transition state and the ligand-substrate steric interactions account for the observed enantioselectivity although the chiral ligand is far away from the to-be-genetated chiral center.

SUBMITTER: Yuan Y

PROVIDER: S-EPMC8161143 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Catalytic enantioselective allene-anhydride approach to β,γ-unsaturated enones bearing an α-all-carbon-quarternary center.

Yuan Yuan Y Zhang Xue X Qian Hui H Ma Shengming S

Chemical science 20200722 34

A protocol of highly regio- and enantioselective copper-catalyzed hydroacylation of the non-terminal C[double bond, length as m-dash]C bond in 1,1-disubstituted terminal allenes with anhydrides has been developed. Both aromatic and aliphatic carboxylic anhydrides are applicable to the efficient construction of all carbon quarternary centers connected with a versatile C[double bond, length as m-dash]C bond and a useful ketone functionality. The synthetic potentials of the enantioenriched products ...[more]

PMID: 34094192

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