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N-Heterocyclic Carbene Ligand-Enabled C(sp(3))-H Arylation of Piperidine and Tetrahydropyran Derivatives.

ABSTRACT: Pd(II)-catalyzed C(sp(3))-H arylation of saturated heterocycles with a wide range of aryl iodides is enabled by an N-heterocyclic carbene (NHC) ligand. A C(sp(3))-H insertion step by the Pd(II)/NHC complex in the absence of ArI is demonstrated experimentally for the first time. Experimental data suggests that the previously established NHC-mediated Pd(0)/Pd(II) catalytic manifold does not operate in this reaction. This transformation provides a new approach for diversifying pharmaceutically relevant piperidine and tetrahydropyran ring systems.

SUBMITTER: Ye S

PROVIDER: S-EPMC4805524 | biostudies-literature | 2016 Mar

REPOSITORIES: biostudies-literature

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N-Heterocyclic Carbene Ligand-Enabled C(sp(3))-H Arylation of Piperidine and Tetrahydropyran Derivatives.

Ye Shengqing S Yang Weibo W Coon Timothy T Fanning Dewey D Neubert Tim T Stamos Dean D Yu Jin-Quan JQ

Chemistry (Weinheim an der Bergstrasse, Germany) 20160224 14

Pd(II)-catalyzed C(sp(3))-H arylation of saturated heterocycles with a wide range of aryl iodides is enabled by an N-heterocyclic carbene (NHC) ligand. A C(sp(3))-H insertion step by the Pd(II)/NHC complex in the absence of ArI is demonstrated experimentally for the first time. Experimental data suggests that the previously established NHC-mediated Pd(0)/Pd(II) catalytic manifold does not operate in this reaction. This transformation provides a new approach for diversifying pharmaceutically rele ...[more]

PMID: 26841330

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