Enantioselective hydrogenation of α-β-unsaturated ketones

A. Tungler, M. Kajtar, T. Mathe, G. Toth, E. Fogassy, J. Petro

Research output: Contribution to journalArticle

61 Citations (Scopus)

Abstract

In the asymmetric synthesis of chiral compounds the reduction of prochiral unsaturated reactants has a great importance. The use of proline as a chiral agent in hydrogenations, where the proline is applied as homogeneous chiral catalyst in ring-closure reactions of triketones, was reported previously. In this paper Proline is used in the hydrogenations of α-β unsaturated ketones or acetophenone with palladium on carbon catalysts, producing saturated ketones or α-phenyl-ethyl-alcohol of 5-60% optical purity. The influence of parameters on optical yield is also investigated. UV, NMR and circular dichroism measurements allow to propose the following mechanism: the zwitterionic form of proline gives a Schiff-base or enamin with the ketones; in the hydrogenation of this compound asymmetric induction takes place, which results in optically active ketones after hydrolizing the saturated product.

Original languageEnglish
Pages (from-to)159-171
Number of pages13
JournalCatalysis Today
Volume5
Issue number2
DOIs
Publication statusPublished - 1989

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Ketones
Proline
Hydrogenation
Catalysts
Schiff Bases
Palladium
Dichroism
Ethanol
Carbon
Nuclear magnetic resonance

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Enantioselective hydrogenation of α-β-unsaturated ketones. / Tungler, A.; Kajtar, M.; Mathe, T.; Toth, G.; Fogassy, E.; Petro, J.

In: Catalysis Today, Vol. 5, No. 2, 1989, p. 159-171.

Research output: Contribution to journalArticle

Tungler, A. ; Kajtar, M. ; Mathe, T. ; Toth, G. ; Fogassy, E. ; Petro, J. / Enantioselective hydrogenation of α-β-unsaturated ketones. In: Catalysis Today. 1989 ; Vol. 5, No. 2. pp. 159-171.
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