Full Paper
Mechanistic aspects of dihydrogen activation and transfer during asymmetric hydrogenation in supercritical carbon dioxide
Susanne Lange,
Axel Brinkmann,
Peter Trautner,
Klaus Woelk,
Joachim Bargon,
Walter Leitner,
Susanne Lange
Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr, Germany
Search for more papers by this authorAxel Brinkmann
Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr, Germany
Search for more papers by this authorPeter Trautner
Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn, Germany
Search for more papers by this authorKlaus Woelk
Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn, Germany
Search for more papers by this authorJoachim Bargon
Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn, Germany
Search for more papers by this authorCorresponding Author
Walter Leitner
Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr, Germany
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim/Ruhr, GermanySearch for more papers by this authorSusanne Lange,
Axel Brinkmann,
Peter Trautner,
Klaus Woelk,
Joachim Bargon,
Walter Leitner,
Susanne Lange
Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr, Germany
Search for more papers by this authorAxel Brinkmann
Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr, Germany
Search for more papers by this authorPeter Trautner
Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn, Germany
Search for more papers by this authorKlaus Woelk
Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn, Germany
Search for more papers by this authorJoachim Bargon
Institut für Physikalische und Theoretische Chemie, Universität Bonn, Bonn, Germany
Search for more papers by this authorCorresponding Author
Walter Leitner
Max-Planck-Institut für Kohlenforschung, Mülheim/Ruhr, Germany
Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim/Ruhr, GermanySearch for more papers by this authorFirst published: 19 May 2000
Citations: 52
Abstract
A new ”CO2-philic” chiral rhodium diphosphinite complex was synthesized and applied as catalyst precursor in the asymmetric hydrogenation of dimethyl itaconate in scCO2, scC2H6 and various liquid organic solvents. Deuterium labeling studies and parahydrogen-induced polarization (PHIP) NMR experiments were used to provide the first detailed mechanistic insight into the activation and transfer of the dihydrogen molecule during hydrogenation in scCO2. Chemical interactions between CO2 and reactive intermediates of the catalytic pathway could be excluded as possible explanations for the experimentally verified difference in the catalytic behavior in scCO2 and hexane. Chirality 12:450–457, 2000 © 2000 Wiley-Liss, Inc.
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