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Unexpected ortho-Heck Reaction under the Catellani Conditions.

ABSTRACT: An unexpected ortho-Heck reaction has been discovered during the study of palladium/norbornene (Pd/NBE) catalysis. Under the Catellani reaction conditions in the presence of lithium salts and olefins, Heck coupling takes place at the ortho position instead of the commonly observed ipso position; meanwhile, a norbornyl group is introduced at the arene ipso position. Systematic deuterium labeling and crossover experiments suggest an unusual 1,4-palladium migration/intramolecular hydrogen transfer pathway. The knowledge gained in this study could provide insights for the future development of the Pd/NBE catalysis.

SUBMITTER: Rago AJ

PROVIDER: S-EPMC7945955 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Unexpected <i>ortho</i>-Heck Reaction under the Catellani Conditions.

Rago Alexander J AJ Dong Guangbin G

Organic letters 20200402 10

An unexpected <i>ortho</i>-Heck reaction has been discovered during the study of palladium/norbornene (Pd/NBE) catalysis. Under the Catellani reaction conditions in the presence of lithium salts and olefins, Heck coupling takes place at the ortho position instead of the commonly observed ipso position; meanwhile, a norbornyl group is introduced at the arene ipso position. Systematic deuterium labeling and crossover experiments suggest an unusual 1,4-palladium migration/intramolecular hydrogen tr ...[more]

PMID: 32239958

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