Crown ethers in enantioselective synthesis

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

A number of new chiral crown compounds and lariat ethers have been synthesized starting from phenyl-β-D-glucopyranoside, methyl-α-D- glucopyranoside and galactopyranoside, methyl-α-D-mannopyranoside and 1,2:5,6-di-O-isopropylidene-D-mannitol, but the main emphasis was laid on their application. Some of the sugar-based macrocycles showed significant asymmetric induction as phase transfer catalysts in liquid-liquid and solid-liquid phase reactions such as in two Michael addition reactions (84-95 % ee), in a Darzens condensation (74 % ee) and in the epoxidation of chalcones (92 % ee). The proposed mechanism of the selective reactions was supported by molecular mechanics calculations. The asymmetric self-condensation of phenacyl chloride took place in 64 % ee value. A novel deracemization of CH-acids has also been discovered and the reason of the enantioselective protonation is discussed.

Original languageEnglish
Pages (from-to)349-358
Number of pages10
JournalKemija u industriji/Journal of Chemists and Chemical Engineers
Volume53
Issue number7-8
Publication statusPublished - Jul 2004

Fingerprint

Crown Ethers
Crown ethers
Crown Compounds
Condensation
Liquids
Chalcones
Addition reactions
Molecular mechanics
Ethers
Epoxidation
Protonation
Mannitol
Sugars
Chlorides
Catalysts
Acids

Keywords

  • Asymmetric phase transfer catalysis
  • Chiral crown ethers
  • Chiral lariat ethers
  • Enantioselective induction

ASJC Scopus subject areas

  • Chemical Engineering(all)

Cite this

Crown ethers in enantioselective synthesis. / Tőke, L.; Bakó, P.; Keglevich, G.; Bakó, T.

In: Kemija u industriji/Journal of Chemists and Chemical Engineers, Vol. 53, No. 7-8, 07.2004, p. 349-358.

Research output: Contribution to journalArticle

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