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Expedient Access to 2,3-Dihydropyridines from Unsaturated Oximes by Rh(III)-Catalyzed C-H Activation.

ABSTRACT: ?,?-Unsaturated oxime pivalates are proposed to undergo reversible C(sp(2))-H insertion with cationic Rh(III) complexes to furnish five-membered metallacycles. In the presence of 1,1-disubstituted olefins, these species participate in irreversible migratory insertion to give, after reductive elimination, 2,3-dihydropyridine products in good yields. Catalytic hydrogenation can then be used to convert these molecules into piperidines, which are important structural components of numerous pharmaceuticals.

SUBMITTER: Romanov-Michailidis F

PROVIDER: S-EPMC4986696 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

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Expedient Access to 2,3-Dihydropyridines from Unsaturated Oximes by Rh(III)-Catalyzed C-H Activation.

Romanov-Michailidis Fedor F Sedillo Kassandra F KF Neely Jamie M JM Rovis Tomislav T

Journal of the American Chemical Society 20150708 28

α,β-Unsaturated oxime pivalates are proposed to undergo reversible C(sp(2))-H insertion with cationic Rh(III) complexes to furnish five-membered metallacycles. In the presence of 1,1-disubstituted olefins, these species participate in irreversible migratory insertion to give, after reductive elimination, 2,3-dihydropyridine products in good yields. Catalytic hydrogenation can then be used to convert these molecules into piperidines, which are important structural components of numerous pharmaceu ...[more]

PMID: 26154248

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