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Palladium(II)-catalyzed enantioselective C(sp³)-H activation using a chiral hydroxamic acid ligand.

ABSTRACT: An enantioselective method for Pd(II)-catalyzed cross-coupling of methylene ?-C(sp(3))-H bonds in cyclobutanecarboxylic acid derivatives with arylboron reagents is described. High yields and enantioselectivities were achieved through the development of chiral mono-N-protected ?-amino-O-methylhydroxamic acid (MPAHA) ligands, which form a chiral complex with the Pd(II) center. This reaction provides an alternative approach to the enantioselective synthesis of cyclobutanecarboxylates containing ?-chiral quaternary stereocenters. This new class of chiral catalysts also show promises for enantioselective ?-C(sp(3))-H activation of acyclic amides.

SUBMITTER: Xiao KJ

PROVIDER: S-EPMC4063184 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

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Palladium(II)-catalyzed enantioselective C(sp³)-H activation using a chiral hydroxamic acid ligand.

Xiao Kai-Jiong KJ Lin David W DW Miura Motofumi M Zhu Ru-Yi RY Gong Wei W Wasa Masayuki M Yu Jin-Quan JQ

Journal of the American Chemical Society 20140519 22

An enantioselective method for Pd(II)-catalyzed cross-coupling of methylene β-C(sp(3))-H bonds in cyclobutanecarboxylic acid derivatives with arylboron reagents is described. High yields and enantioselectivities were achieved through the development of chiral mono-N-protected α-amino-O-methylhydroxamic acid (MPAHA) ligands, which form a chiral complex with the Pd(II) center. This reaction provides an alternative approach to the enantioselective synthesis of cyclobutanecarboxylates containing α-c ...[more]

PMID: 24815880

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