The influence of the reaction conditions on the asymmetric heterogeneous catalytic reaction of 2-nitrophenylpyruvates over Pt modified with cinchonidine showed that all three steps of the cascade occur on the metal surface.

The development of a novel heterogeneous catalytic asymmetric cascade reaction for the synthesis of tetrahydroquinolines from 2-nitrophenylpyruvates is reported. Optically enriched 3-hydroxy-3,4dihydroquinolin-2(1H)-ones are prepared by enantioselective hydrogenation of the activated keto group over a Cinchona alkaloid-modified Pt catalyst, reduction of the nitro group and spontaneous cyclization cascade. Acceleration of the enantioselective hydrogenation of the activated keto group over the catalyst modified by Cinchona alkaloids ensured high tetrahydroquinolinone selectivities. The scope of the reaction was checked using twelve substrates. Both yields and enantioselectivities were significantly influenced by the nature and position of the substituents on the phenyl ring. Substituents adjacent to the nitro group considerably increased the product yield, due to their effect on the nitro group's reduction rate; however, had only a limited effect on enantioselectivities.

The reversal of the enantioselectivity in the heterogeneous asymmetric direct aldol reactions obtained over resin supported di- versus tripeptides was studied in a continuous-flow system.

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