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Choline Chloride-Based Deep Eutectic Systems in Sequential Friedlander Reaction and Palladium-Catalyzed sp3 CH Functionalization of Methyl Ketones.

ABSTRACT: A volatile organic solvent-free and choline chloride (ChCl)-based deep eutectic system (DES)-mediated sp3-CH functionalization of acetophenones 1 with benzyl alcohols 2 to the corresponding ?, ?-saturated ketones 3 is accounted for. The domino dehydrogenation-aldol condensation (hydrogenation borrowing concept) has been successfully attempted with palladium-tetrakis(triphenylphosphine) [Pd(PPh3)4] catalyst-xantphos ligand combination. Furthermore, a sequential Friedländer reaction of 2-aminobenzophenone 4 and palladium-catalyzed ?-alkylation of the quinolinyl methyl ketone with benzyl alcohols 2 in ChCl-based DES have been successfully investigated. The C-C bond formation through sp3-CH functionalization involves a wide scope of the substrates, high atom efficiency, chemoselectivity, and environmentally friendly strategy.

SUBMITTER: Teja C

PROVIDER: S-EPMC6648676 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature

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Choline Chloride-Based Deep Eutectic Systems in Sequential Friedländer Reaction and Palladium-Catalyzed sp3 CH Functionalization of Methyl Ketones.

Teja Chitrala C Nawaz Khan Fazlur Rahman FR

ACS omega 20190502 5

A volatile organic solvent-free and choline chloride (ChCl)-based deep eutectic system (DES)-mediated sp3-CH functionalization of acetophenones 1 with benzyl alcohols 2 to the corresponding α, β-saturated ketones 3 is accounted for. The domino dehydrogenation-aldol condensation (hydrogenation borrowing concept) has been successfully attempted with palladium-tetrakis(triphenylphosphine) [Pd(PPh3)4] catalyst-xantphos ligand combination. Further ...[more]

PMID: 31459894

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