Observation of high enantioselectivity for the gas phase hydrogenation of methyl pyruvate using supported Pt catalysts pre-modified with cinchonidine.
نویسندگان
چکیده
Pt supported on alpha-Al2O3, gamma-Al2O3 and SiO2 pre-modified with cinchonidine gives over 50% ee in the hydrogenation of methyl pyruvate to methyl lactate using gas phase reactants at 40 degrees C giving the first clear observation of high enantioselection at the gas/solid interface.
منابع مشابه
Determination of geometric orientation of adsorbed cinchonidine on Pt and Fe and quiphos on Pt nanoclusters via DRIFTS.
Platinum nanoclusters modified with cinchonidine have been employed as 'quasi-homogeneous' catalysts for the hydrogenation of ethyl pyruvate and have demonstrated exceptional activities while the ee's of these systems are currently inferior to the traditional Pt/Al2O3 heterogeneous system. For the bulk systems it has been shown that the orientation of the modifier on the metal surface is a crit...
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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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ورودعنوان ژورنال:
- Chemical communications
دوره 15 شماره
صفحات -
تاریخ انتشار 2003