Chemo- and diastereoselectivity in the heterogeneous catalytic hydrogenation of 2,2′-pyridoin and its derivatives

Viktor Háda, A. Tungler, L. Szepesy

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

The heterogeneous catalytic hydrogenations of 2,2′-pyridoin and related compounds, such as 2,2′-pyridil and O-acetyl-2,2′-pyridoin, were investigated over noble metal catalysts. The influence of catalytic metals, catalyst supports, solvents, acid additives, prehydrogenation, and hydrogen pressure on the chemo- and diastereoselectivity is discussed in the hydrogenation of 2,2′-pyridoin. Although hydrogenolysis and ring saturation may occur as side reactions, high chemo- (90-100%) and moderate diastereoselectivity values were achieved. Over palladium black in an acetonitrile-water solvent mixture, the hydrogenation resulted in a meso/dl ratio of 72/28, while in the hydrogenation over rhodium on carbon the meso/dl ratio was 29/71. The phenomenon of diastereoselection in the hydrogenation is explained by the stereochemistry of the hydrogen addition, considering the cis-trans isomerization on the catalyst surface, the possible enolization, and the competing C=C and C=O reductions.

Original languageEnglish
Pages (from-to)472-479
Number of pages8
JournalJournal of Catalysis
Volume209
Issue number2
DOIs
Publication statusPublished - 2002

Fingerprint

Hydrogenation
hydrogenation
Derivatives
catalysts
Hydrogen
hydrogenolysis
Hydrogenolysis
Rhodium
Stereochemistry
Catalysts
stereochemistry
Palladium
hydrogen
Precious metals
Isomerization
noble metals
Acetonitrile
rhodium
Catalyst supports
isomerization

Keywords

  • C=C and C=O double bonds
  • cis-trans isomerization
  • Diastereoselectivity
  • Heterogeneous catalytic hydrogenation
  • Hydrogenolysis

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Chemo- and diastereoselectivity in the heterogeneous catalytic hydrogenation of 2,2′-pyridoin and its derivatives. / Háda, Viktor; Tungler, A.; Szepesy, L.

In: Journal of Catalysis, Vol. 209, No. 2, 2002, p. 472-479.

Research output: Contribution to journalArticle

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