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Synthesis of gem-Difluoro Olefins through C-H Functionalization and ?-fluoride Elimination Reactions.

ABSTRACT: A palladium catalyzed C-H functionalization and consecutive ?-fluoride elimination reaction between indole heterocycles and fluorinated diazoalkanes is reported. This approach provides for the first time a facile method for the rapid synthesis of gem-difluoro olefins using fluorinated diazoalkanes under mild reaction conditions. Cyclopropanation products were obtained when N-arylated rather than N-alkylated indoles were applied in this reaction. Mechanistic studies reveal the importance of the ?-fluoride elimination step in this transformation. This method presents a new concept for the simple and direct transfer of a 1-aryl-(2,2-difluorovinyl) group to access gem-difluoro olefins.

SUBMITTER: Yang Z

PROVIDER: S-EPMC7155031 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Synthesis of gem-Difluoro Olefins through C-H Functionalization and β-fluoride Elimination Reactions.

Yang Zhen Z Möller Mieke M Koenigs Rene M RM

Angewandte Chemie (International ed. in English) 20200221 14

A palladium catalyzed C-H functionalization and consecutive β-fluoride elimination reaction between indole heterocycles and fluorinated diazoalkanes is reported. This approach provides for the first time a facile method for the rapid synthesis of gem-difluoro olefins using fluorinated diazoalkanes under mild reaction conditions. Cyclopropanation products were obtained when N-arylated rather than N-alkylated indoles were applied in this reaction. Mechanistic studies reveal the importance of the β ...[more]

PMID: 31885145

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