from first principles PP-I-1

PP-III-80Enantioselective Hydrogenation of С=С-Bound on Colloidal PalladiumCatalyst Modified by (-)-CinchonidineNindakova L.O., Ozolin D.V., Lubentzova K.V.Irkutsk State Technical University, Irkutsk, Russianindakova@istu.eduThe colloid metals are well known as the effective and stereoselective catalysts for C-C-bondformation, ketones and olefins hydrogenation. The metal colloids stabilized by the opticalactive molecules and ions are applicable in the enantioselective transformations of prochiralmolecules, in particular, in the enantioselective hydrogenation of methyl pyruvate that iscatalyzed by the colloidal platinum modified by dihydrocinchonine [1]. The highly dispersedtransition metals in colloidal suspension allow one to study the catalytic properties of thesmall metal particles in an absence of solid supports.In this work, for the enantioselective hydrogenation of dimethyl itaconate (DMIA) and methylα-acetamido cinnammate, we used the chiral cinchona alkaloid such as the widely applied(-)-cinchonidine (Cin) to modify the system Pd(acac) 2 -H 2 that showed the catalytic activity inthe unsaturated C=C-bonds hydrogenation.At ambient temperature, Р Н2 = 5 bar and 100% conversion after 20 hour, the enantiomericexcess (ee) of methyl R-(-)-N-acethyl-α-phenylalanine achieved 78% ee. The figure presentsthe dependence for ee of methyl R-(-)-N-acethyl-α-phenylalanineon (-) Cin/Pd ratio. For dimethyl itaconate hydrogenation, one obtains a moderate result only.Figure. The (-) Cin/Pd ratio influence on the yieldof methyl R-(-)-N-acethyl-α-phenylalanineReferences:[1]. Bonnemann H., Braun G. A. , Chem. Eur. J. 1997, 3, 1200237