Enantioselective Michael addition catalyzed by cinchona alkaloids

Research output: Contribution to journalArticle

29 Citations (Scopus)

Abstract

Enantioselective Michael additions of cyclic β-ketoesters to methyl vinyl ketone catalyzed by cinchona alkaloids were studied. The results revealed that the induced enantioselectivity was significantly influenced by both the structure of the catalyst and that of the substrate. Interesting differences in the effect of the structure of the alkaloid on the enantioselectivity of this reaction in the case of three β-ketoesters were discovered. High enantioselectivities were obtained in the reaction of ethyl 2-oxocyclo-pentanecarboxylate and ethyl 2-oxocyclohexanecarboxylate (up to 83 and 80%, respectively) at a low cinchona:reactant ratio of 1:500. As the specific rotations of the product enantiomers were unknown, they were determined by optical rotation and chiral GC measurements and verified by NMR experiments.

Original languageEnglish
Pages (from-to)614-618
Number of pages5
JournalChirality
Volume13
Issue number10
DOIs
Publication statusPublished - 2001

Fingerprint

Cinchona
Cinchona Alkaloids
Optical Rotation
Enantioselectivity
Alkaloids
Optical rotation
Enantiomers
Ketones
Nuclear magnetic resonance
Catalysts
Substrates
3-buten-2-one
Experiments

Keywords

  • β-ketoesters
  • Cinchona alkaloids
  • Enantioselectivity
  • Methyl vinyl ketone
  • Michael addition

ASJC Scopus subject areas

  • Analytical Chemistry
  • Drug Discovery
  • Organic Chemistry
  • Pharmacology

Cite this

Enantioselective Michael addition catalyzed by cinchona alkaloids. / Szöllősi, G.; Bartók, M.

In: Chirality, Vol. 13, No. 10, 2001, p. 614-618.

Research output: Contribution to journalArticle

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