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Palladium-catalyzed asymmetric conjugate addition of arylboronic acids to five-, six-, and seven-membered ?-substituted cyclic enones: enantioselective construction of all-carbon quaternary stereocenters.

ABSTRACT: The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4-addition of arylboronic acids to ?-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF(3))(2) and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this transformation is tolerant to air and moisture, providing a practical and operationally simple method of synthesizing enantioenriched all-carbon quaternary stereocenters.

SUBMITTER: Kikushima K

PROVIDER: S-EPMC3087848 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Palladium-catalyzed asymmetric conjugate addition of arylboronic acids to five-, six-, and seven-membered β-substituted cyclic enones: enantioselective construction of all-carbon quaternary stereocenters.

Kikushima Kotaro K Holder Jeffrey C JC Gatti Michele M Stoltz Brian M BM

Journal of the American Chemical Society 20110415 18

The first enantioselective Pd-catalyzed construction of all-carbon quaternary stereocenters via 1,4-addition of arylboronic acids to β-substituted cyclic enones is reported. Reaction of a wide range of arylboronic acids and cyclic enones using a catalyst prepared from Pd(OCOCF(3))(2) and a chiral pyridinooxazoline ligand yields enantioenriched products bearing benzylic stereocenters. Notably, this transformation is tolerant to air and moisture, providing a practical and operationally simple meth ...[more]

PMID: 21495647

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