caa a22 4500 47584422X CHVBK 20180406123909.0 cr unu---uuuuu 170329e20000801xx s 000 0 eng 10.1023/A:1009097225184 doi (NATIONALLICENCE)springer-10.1023/A:1009097225184 Establishment and maintenance of an optimal chiral surface in cinchona-modified 1% Pt/Al2O3 for enantioselective hydrogenation of α-keto esters [Elektronische Daten] [C. LeBlond, J. Wang, A.T. Andrews, Y.-K. Sun] An optimal chiral surface in the cinchona-modified Pt/Al2O3 catalytic system is established for fast enantioselective hydrogenation of ethyl pyruvate. A makeup protocol is used to compensate for the destructive hydrogenation of the chiral modifier, thus maintaining the optimal chiral surface over the course of the hydrogenation reaction. Hydrogenation over the optimal surface (Ptsurface/modifier = 5-12) results in high enantioselectivity (94% ee) under mild conditions (5.8 bar and 17°C) with high turnover frequency (4 s-1) and turnover numbers (pyruvate/modifier>28,000, pyruvate/Ptsurface>5,500). Kluwer Academic Publishers, 2000 solid chiral catalyst nationallicence α-keto ester nationallicence pyruvate nationallicence enantioselective hydrogenation nationallicence cinchona nationallicence Pt/Al2O3 nationallicence LeBlond C. Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut Wang J. Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut Andrews A.T. Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut Sun Y.-K Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut Topics in Catalysis Kluwer Academic Publishers-Plenum Publishers 13/3(2000-08-01), 169-174 1022-5528 13:3<169 2000 13 11244 https://doi.org/10.1023/A:1009097225184 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1009097225184 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- LeBlond C. Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut NATIONALLICENCE 700 1- Wang J. Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut NATIONALLICENCE 700 1- Andrews A.T. Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut NATIONALLICENCE 700 1- Sun Y.-K Merck Research Laboratories, PO Box 2000, 07065, Rahway, NJ, USA aut NATIONALLICENCE 773 0- Topics in Catalysis Kluwer Academic Publishers-Plenum Publishers 13/3(2000-08-01), 169-174 1022-5528 13:3<169 2000 13 11244 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer