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Ni-Catalyzed Enantioselective C-Acylation of ?-Substituted Lactams.

ABSTRACT: A new strategy for catalytic enantioselective C-acylation to generate ?-quaternary-substituted lactams is reported. Ni-catalyzed three-component coupling of lactam enolates, benzonitriles, and aryl halides produces ?-imino lactams that then afford ?-keto lactams by acid hydrolysis. Use of a readily available Mandyphos-type ligand and addition of LiBr enable the construction of quaternary stereocenters on ?-substituted lactams to form ?-keto lactams in up to 94% ee.

SUBMITTER: Hayashi M

PROVIDER: S-EPMC4963289 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Ni-Catalyzed Enantioselective C-Acylation of α-Substituted Lactams.

Hayashi Masaki M Bachman Shoshana S Hashimoto Satoshi S Eichman Chad C CC Stoltz Brian M BM

Journal of the American Chemical Society 20160715 29

A new strategy for catalytic enantioselective C-acylation to generate α-quaternary-substituted lactams is reported. Ni-catalyzed three-component coupling of lactam enolates, benzonitriles, and aryl halides produces β-imino lactams that then afford β-keto lactams by acid hydrolysis. Use of a readily available Mandyphos-type ligand and addition of LiBr enable the construction of quaternary stereocenters on α-substituted lactams to form β-keto lactams in up to 94% ee. ...[more]

PMID: 27373124

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