Interaction of Cinchonidine and 1-Phenyl-1,2-Propanedione on the Surface of a Chirally Modified Pt/Al2O3 Hydrogenation Catalyst
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- 作者：Igor Busygin ; Olga P. Tkachenko ; Ville Nieminen ; Victor Yu. Borovkov ; Reijo Sillanpä ; ä ; Esa Toukoniitty ; Leonid M. Kustov ; Dmitry Yu. Murzin ; Reko Leino
- 刊名：Journal of Physical Chemistry C
- 出版年：2007
- 出版时间：July 5, 2007
- 年：2007
- 卷：111
- 期：26
- 页码：9374 - 9383
- 全文大小：308K
- 年卷期：v.111,no.26(July 5, 2007)
- ISSN：1932-7455
文摘
Enantioselective hydrogenation of 1-phenyl-1,2-propanedione (PPD) over cinchona-modified oxide-supportedplatinum catalysts represents an extension to the well-known Orito reaction with methyl and ethyl pyruvates(EtPy) as typical substrates for the asymmetric reduction. In this paper, the adsorption of PPD and cinchonidineon a Pt catalyst was studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). Thecatalyst preparation and the adsorption of the reactant and modifier were carried out according to the proceduregenerally used in catalysis under actual reaction conditions. The catalysts with adsorbed species were analyzedex situ. The selective deposition of cinchonidine and PPD on the metal surface was confirmed by parallelexperiments with alumina samples and by analyzing the platinum adsorption sites with carbon monoxide asa probe molecule. Among the IR visible adsorbed species, 
1(O2)-configuration of PPD was found as themost populated on Pt surface under the conditions of ex situ measurements. New data on the mutual interactionsamong cinchonidine, PPD, and the Pt catalyst are presented. Tilted 
pi.gif" BORDER=0 >-bonded cinchonidine was detected onthe surface under the modifier concentration profile used for obtaining high enantioselectivity in thehydrogenation of PPD. Hydrogen bonding between adsorbed cinchonidine and PPD was also detected.
1(O2)-configuration of PPD was found as themost populated on Pt surface under the conditions of ex situ measurements. New data on the mutual interactionsamong cinchonidine, PPD, and the Pt catalyst are presented. Tilted pi.gif" BORDER=0 >-bonded cinchonidine was detected onthe surface under the modifier concentration profile used for obtaining high enantioselectivity in thehydrogenation of PPD. Hydrogen bonding between adsorbed cinchonidine and PPD was also detected.