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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 | 2022 May

REPOSITORIES: biostudies-literature

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

Galiana-Cameo María M Romeo Raúl R Urriolabeitia Asier A Passarelli Vincenzo V Pérez-Torrente Jesús J JJ Polo Victor V Castarlenas Ricardo R

Angewandte Chemie (International ed. in English) 20220319 20

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 rele ...[more]

PMID: 35262264

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