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Rhodium-NHC-Catalyzed gem-Specific O-Selective Hydropyridonation of Terminal Alkynes.

ABSTRACT: The dinuclear complex [Rh(μ-Cl)(η² -coe)(IPr)]₂ is an efficient catalyst for the O-selective Markovnikov-type addition of 2-pyridones to terminal alkynes. DFT calculations support a hydride-free pathway entailing intramolecular oxidative protonation of a π-alkyne by a κ¹ N-hydroxypyridine ligand. Subsequent O-nucleophilic attack on a metallacyclopropene species affords an O-alkenyl-2-oxypyridine chelate rhodium intermediate as the catalyst resting state. The release of the alkenyl ether is calculated as the rate-determining step.

SUBMITTER: Galiana-Cameo M

PROVIDER: S-EPMC9311084 | biostudies-literature |

REPOSITORIES: biostudies-literature

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