88126-34-5Relevant academic research and scientific papers
Enantiomeric products formed via different mechanisms: asymmetric hydrogenation of an α,β-unsaturated carboxylic acid involving a Ru(CH3COO)2[(R)-binap] catalyst
Yoshimura, Masahiro,Ishibashi, Yoshitaka,Miyata, Kengo,Bessho, Yuhki,Tsukamoto, Masaki,Kitamura, Masato
, p. 11399 - 11409 (2008/03/13)
Hydrogenation of (Z)-3-phenyl-2-butenoic acid with a Ru(CH3COO)2[(R)-binap] (BINAP=2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) catalyst in methanol gives (S)-3-phenyl-2-butanoic acid and its R enantiomer in a 97:3 (4 atm) to 94:6 (100 atm) ratio in quantitative yield. Both hydrogen gas and protic methanol participate in the saturation of the olefinic bond. Analysis of the products obtained using (Z)-3-phenyl-2-butenoic acid-3-13C and either H2, a 1:1 H2-D2 mixture, or D2 in CH3OD indicates that several catalytic cycles are operative, showing different reactivity and stereoselectivity. The major S enantiomer was formed primarily by the standard Ru monohydride mechanism, whereas the minor R isomer is produced via more complicated routes.
Origin of the minor enantiomeric product in a noyori asymmetric hydrogenation: Evidence for pathways different to the major mechanism
Ishibashi, Yoshitaka,Bessho, Yuhki,Yoshimura, Masahiro,Tsukamoto, Masaki,Kitamura, Masato
, p. 7287 - 7290 (2007/10/03)
(Chemical Equation Presented) Hidden pathways: The enantiomeric products of the catalytic hydrogenation of an isotopically labeled substrate were separated. The ratios of the isotopomers revealed that the major and minor enantiomers are formed mostly through different mechanisms. Hence, when analyzing the energy profile of an asymmetric catalytic reaction with the Arrhenius equation, two competing diastereomorphic catalytic cycles should be considered (see scheme).
