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N-Aminopyridinium Ylide-Directed, Copper-Promoted Amination of sp2 C-H Bonds.

ABSTRACT: N-Aminopyridinium ylides are used as monodentate directing groups for copper-promoted C-H/N-H coupling of sp2 C-H bonds with pyrazoles, imidazoles, and sulfonamides. Reactions proceed in fluorinated alcohol solvents at elevated temperatures and require use of 1.3-3 equiv of copper(II) acetate. This appears to be the first method for copper-promoted C-H/N-H coupling directed by a removable monodentate auxiliary in absence of added ligands.

SUBMITTER: Kwak SH

PROVIDER: S-EPMC6892399 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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N-Aminopyridinium Ylide-Directed, Copper-Promoted Amination of sp2 C-H Bonds.

Kwak Se Hun SH Daugulis Olafs O

The Journal of organic chemistry 20190910 20

N-Aminopyridinium ylides are used as monodentate directing groups for copper-promoted C-H/N-H coupling of sp2 C-H bonds with pyrazoles, imidazoles, and sulfonamides. Reactions proceed in fluorinated alcohol solvents at elevated temperatures and require use of 1.3-3 equiv of copper(II) acetate. This appears to be the first method for copper-promoted C-H/N-H coupling directed by a removable monodentate auxiliary in absence of added ligands. ...[more]

PMID: 31502845

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