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Asymmetric Michael Addition Organocatalyzed by ?,?-Dipeptides under Solvent-Free Reaction Conditions.

ABSTRACT: The application of six novel ?,?-dipeptides as chiral organocatalysts in the asymmetric Michael addition reaction between enolizable aldehydes and N-arylmaleimides or nitroolefins is described. With N-arylmaleimides as substrates, the best results were achieved with dipeptide 2 as a catalyst in the presence of aq. NaOH. Whereas dipeptides 4 and 6 in conjunction with 4-dimethylaminopyridine (DMAP) and thiourea as a hydrogen bond donor proved to be highly efficient organocatalytic systems in the enantioselective reaction between isobutyraldehyde and various nitroolefins.

SUBMITTER: Avila-Ortiz CG

PROVIDER: S-EPMC6152315 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Asymmetric Michael Addition Organocatalyzed by α,β-Dipeptides under Solvent-Free Reaction Conditions.

Avila-Ortiz C Gabriela CG Díaz-Corona Lenin L Jiménez-González Erika E Juaristi Eusebio E

Molecules (Basel, Switzerland) 20170810 8

The application of six novel α,β-dipeptides as chiral organocatalysts in the asymmetric Michael addition reaction between enolizable aldehydes and N-arylmaleimides or nitroolefins is described. With N-arylmaleimides as substrates, the best results were achieved with dipeptide 2 as a catalyst in the presence of aq. NaOH. Whereas dipeptides 4 and 6 in conjunction with 4-dimethylaminopyridine (DMAP) and thiourea as a hydrogen bond donor proved to be highly efficie ...[more]

PMID: 28796165

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