Multiphase heterogeneous catalytic enantioselective hydrogenation of acetophenone over cinchona-modified Pt/C
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چکیده
منابع مشابه
Heterogeneous enantioselective hydrogenation over cinchona alkaloid modified platinum: mechanistic insights into a complex reaction.
Modification of a metal surface by a strongly adsorbed chiral organic molecule has proven to be an interesting strategy for heterogeneous chiral catalysis. Platinum chirally modified by cinchona alkaloids, successfully applied for the enantioselective hydrogenation of alpha-ketoesters, is probably the most prominent catalyst based on this concept. Despite considerable research efforts toward un...
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The enantioselective hydrogenation of 4-hydroxy-6-methyl-2pyrone in the presence of acetic acid and trifluoroacetic acid has been studied on cinchonidine-modified Pd/TiO2. Catalytic experiments and theoretical calculations indicate the formation of a cinchonidine–trifluoroacetic acid cyclic ion pair. We propose that this is the actual modifier, which interacts with 4-hydroxy-6-methyl2-pyrone in...
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The Pd(111) crystal was attached to a motorized manipulator using tantalum wires and could be heated by means of electron bombardment to 900 K or cooled to 77 K, as monitored by a T1T2 thermocouple attached directly to the sample. It was cleaned by cycles of Ar sputtering (4 keV, 7 μA) and annealing (850 K) followed by brief heating to ~ 850 K in the presence of 2×10 mbar of O2 to remove residu...
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Heterogeneous catalytic hydrogenation of cyclohexene, catalyzed by Pt/A1203, was carried out in thirteenvarious solvents (four alcoholic solvents, six aprotic polar solvents and three non polar solvents) at 25 °C.Single-parameter correlations of logk vs. normalized polarity parameter (ETN), hydrogen-bond acceptorbasicity (p), hydrogen-bond donor acidity (a) and dipolarity/polarizibility (it*) d...
متن کاملEnantioselective hydrogenation of isoquinolines.
Asymmetric hydrogenation of (hetero)arenes is one of the most straightforward ways to synthesize enantiomerically pure, saturated or partially saturated cyclic molecules. Recent progress has significantly expanded the substrate scope of this reaction. Whereas a number of highly efficient catalytic systems have been found for the asymmetric hydrogenation of quinolines, structurally related isoqu...
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ژورنال
عنوان ژورنال: Journal of Molecular Catalysis A: Chemical
سال: 2002
ISSN: 1381-1169
DOI: 10.1016/s1381-1169(01)00423-x