Enantioselective Hydrogenation of Olefins using Commercially Available Pd/C. Chiral Heterogeneous Catalyst Applicable for High-Throughput Screening

Cinchonidine-modified Pd/C applicable for the high-throughput-guided study was developed. Commercial Pd/C catalysts were employed for the enantioselective hydrogenation of phenylcinnamic acid after the pretreatment, and some of the catalysts were found to result in the sufficient enantioselectivity. The Pd/C catalysts suitable for the cinchonidine modification were characterized by TEM and XAFS to have highly dispersed metal, 2.2 nm of the mean particles size for the best catalyst. The pre-modified Pd/C could be stored in a suspension accompanying with gradual decease in the product ee. The pre-modified catalyst was applicable for the high-throughput screening by using a parallel reactor in the 1/5-scale reactions.