Quantitative expression of dynamic kinetic resolution of chirally labile enantiomers: Stereoselective hydrogenation of 2-substituted 3-oxo carboxylic esters catalyzed by BINAP-ruthenium(II) complexes

Journal Article · Wed Jan 13 00:00:00 EST 1993 · Journal of the American Chemical Society; (United States)

DOI:https://doi.org/10.1021/ja00054a020· OSTI ID:6483206

Kitamura, M; Tokunaga, M; Noyori, R ^[1]

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1. Nagoya Univ. (Japan)

Hydrogenation of chirally unstable 2-substituted 3-oxo carboxylic esters gives a mixture of four stereoisomeric hydroxy esters. Use of BINAP-Ru(II) complex catalysts allows selective production of one stereoisomer among four possible isomers. The stereoselectivity obtained by the dynamic kinetic resolution depends on facile in situ racemization of the substrates, efficient chirality recognition ability of the catalysts, and the structures of the ketonic substrate. The factors controlling the efficiency of the stereoselective hydrogenation are experimentally determined by reaction of racemic oxo esters using enantiomerically pure and racemic BINAP complexes. Quantitative expression of the dynamic kinetic resolution has been made by defining the product partition coefficients (w, x, y, and z), the relative reactivities of the enantiomeric substrates (k[sub fast]/k[sub slow]), and the relative ease with which stereoinversion and hydrogenation take place (k[sub inv]/k[sub fast]). The validity of the equations has been demonstrated by the graphical exhibition of the enantioselectivity and diastereoselectivity as a function of conversion of the substrates. 18 refs., 4 figs., 3 tabs.

• OSTI ID: 6483206
• Journal Information: Journal of the American Chemical Society; (United States), Vol. 115:1; ISSN 0002-7863
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ESTERS
HYDROGENATION
RUTHENIUM COMPLEXES
CATALYTIC EFFECTS
CHEMICAL REACTION KINETICS
CHIRALITY
ISOMERS
MATHEMATICAL MODELS
RACEMIZATION
STEREOCHEMISTRY
SUBSTRATES
CHEMICAL REACTIONS
COMPLEXES
KINETICS
ORGANIC COMPOUNDS
PARTICLE PROPERTIES
REACTION KINETICS
TRANSITION ELEMENT COMPLEXES
400201* - Chemical & Physicochemical Properties