Organic compounds -- part of the class 532-570 series – Organic compounds – Carboxylic acid esters
Reexamination Certificate
2006-06-06
2006-06-06
Zucker, Paul A. (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carboxylic acid esters
Reexamination Certificate
active
07057064
ABSTRACT:
The present invention relates to a continuous process for the enantioselective catalytic hydrogenation of β-ketoesters comprising providing a catalytic hydrogenation zone and maintaining it under conditions of temperature and pressure effective for the catalytic hydrogenation of β-ketoesters; continuously supplying to the catalytic hydrogenation zone a substrate comprising a β-ketoester to be hydrogenated, a catalyst effective for enantioselective hydrogenation of the β-ketoester and hydrogen; contacting the substrate, the catalyst and the hydrogen in the hydrogenation zone for a residence time effective for at least partial enantioselective catalytic hydrogenation of the β-ketoester; (d) continuously withdrawing from the hydrogenation zone a reaction product mixture comprising enantioselectively hydrogenated β-ketoester, unreacted β-ketoester, catalyst and hydrogen; (e) supplying the reaction product mixture to a separation zone and separating at least some of the enantioselectively hydrogenated β-ketoester from the reaction product mixture; (f) withdrawing the separated enantioselectively hydrogenated β-ketoester as product; and (g) optionally supplying at least part of the remaining material from the separation zone to the hydrogenation zone.
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Proctor Lee David
Warr Anthony John
Brooks & Kushman P.C.
Phoenix Chemicals Limited
Zucker Paul A.
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