A NEW CHIRAL AUXILIARY IN ENANTIOSELECTIVE HYDROGENATIONS - (-)-DIHYDROVINPOCETINE - HYDROGENATION OF ETHYL PYRUVATE .2.

Authors
TUNGLER A MATHE T FODOR K SHELDON RA GALLEZOT P
Citation
A. Tungler et al., A NEW CHIRAL AUXILIARY IN ENANTIOSELECTIVE HYDROGENATIONS - (-)-DIHYDROVINPOCETINE - HYDROGENATION OF ETHYL PYRUVATE .2., Journal of molecular catalysis. A, Chemical, 108(3), 1996, pp. 145-151
Citations number
8
Categorie Soggetti
Chemistry Physical
Journal title
Journal of molecular catalysis. A, Chemical → ACNP
ISSN journal
13811169
Volume
108
Issue
3
Year of publication
1996
Pages
145 - 151
Database
ISI
SICI code
1381-1169(1996)108:3<145:ANCAIE>2.0.ZU;2-2
Abstract
A vinca-type synthetic alkaloid: (-)-dihydrovinpocetine functions as a chiral auxiliary in the enantioselective hydrogenation of the C=O gro up of ethyl pyruvate. Various catalysts, supports, solvents have been screened. The effect of modifier's concentration, acetic acid additive and of combined modifiers (+ dihydro-cinchonidine and -cinchonine) is described. The highest optical yield (30%) is obtained with a Pt on a lumina catalyst, Mechanistic considerations and comparison with the kn own Pt/cinchona system have been made.