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Ligand-Enabled ?-C(sp(3))-H Olefination of Amines: En Route to Pyrrolidines.

ABSTRACT: Pd(II)-catalyzed olefination of ?-C(sp(3))-H bonds of triflyl (Tf) and 4-nitrobenzenesulfonyl (Ns) protected amines is achieved. Subsequent aza-Wacker oxidative cyclization or conjugate addition of the olefinated intermediates provides a variety of C-2 alkylated pyrrolidines. Three pyridine- and quinoline-based ligands are developed to match different classes of amine substrates, demonstrating a rare example of ligand-enabled C(sp(3))-H olefination reactions. The use of Ns protecting group to direct C(sp(3))-H activation of alkyl amines is also a significant step toward practical C-H functionalizations of alkyl amines.

SUBMITTER: Jiang H

PROVIDER: S-EPMC4817546 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Ligand-Enabled γ-C(sp(3))-H Olefination of Amines: En Route to Pyrrolidines.

Jiang Heng H He Jian J Liu Tao T Yu Jin-Quan JQ

Journal of the American Chemical Society 20160204 6

Pd(II)-catalyzed olefination of γ-C(sp(3))-H bonds of triflyl (Tf) and 4-nitrobenzenesulfonyl (Ns) protected amines is achieved. Subsequent aza-Wacker oxidative cyclization or conjugate addition of the olefinated intermediates provides a variety of C-2 alkylated pyrrolidines. Three pyridine- and quinoline-based ligands are developed to match different classes of amine substrates, demonstrating a rare example of ligand-enabled C(sp(3))-H olefination reactions. The use of Ns protecting group to di ...[more]

PMID: 26796676

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