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Rhodium-catalyzed regioselective addition of the ortho C-H bond in aromatic amides to the C-C double bond in ?,?-unsaturated ?-lactones and dihydrofurans.

ABSTRACT: An unprecedented C-H alkylation using ?,?-unsaturated ?-lactones (butenolides) and dihydrofurans was achieved by the Rh-catalyzed reaction of benzamides. C-C bond formation occurs between the ortho-position of the benzamide derivative and the ?-position of the butenolide or the ?-position of the dihydrofuran. The presence of an 8-aminoquinoline directing group is crucial for the success of the reaction. The results of deuterium labeling experiments indicate that the cleavage of the C-H bond is reversible and suggest that a migratory carbene insertion is involved as the key step.

SUBMITTER: Shibata K

PROVIDER: S-EPMC5952307 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Rhodium-catalyzed regioselective addition of the ortho C-H bond in aromatic amides to the C-C double bond in α,β-unsaturated γ-lactones and dihydrofurans.

Shibata Kaname K Chatani Naoto N

Chemical science 20150925 1

An unprecedented C-H alkylation using α,β-unsaturated γ-lactones (butenolides) and dihydrofurans was achieved by the Rh-catalyzed reaction of benzamides. C-C bond formation occurs between the ortho-position of the benzamide derivative and the γ-position of the butenolide or the α-position of the dihydrofuran. The presence of an 8-aminoquinoline directing group is crucial for the success of the reaction. The results of deuterium labeling experiments indicate that the cleavage of the C-H bo ...[more]

PMID: 29861979

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