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Mechanistic comparison between Pd-catalyzed ligand-directed C-H chlorination and C-H acetoxylation.

ABSTRACT: This communication describes detailed investigations of the mechanism of the Pd-catalyzed C-H chlorination and acetoxylation of 2-o-tolylpyridine. Under the conditions examined, both reactions proceed via rate-limiting cyclopalladation. However, substrate and catalyst order as well as Hammett data indicate that the intimate mechanism of cyclopalladation differs significantly between PdCl2-catalyzed chlorination and Pd(OAc)2-catalyzed acetoxylation.

SUBMITTER: Stowers KJ

PROVIDER: S-EPMC2778044 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Mechanistic comparison between Pd-catalyzed ligand-directed C-H chlorination and C-H acetoxylation.

Stowers Kara J KJ Sanford Melanie S MS

Organic letters 20091001 20

This communication describes detailed investigations of the mechanism of the Pd-catalyzed C-H chlorination and acetoxylation of 2-o-tolylpyridine. Under the conditions examined, both reactions proceed via rate-limiting cyclopalladation. However, substrate and catalyst order as well as Hammett data indicate that the intimate mechanism of cyclopalladation differs significantly between PdCl2-catalyzed chlorination and Pd(OAc)2-catalyzed acetoxylation. ...[more]

PMID: 19754074

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