Cooperative Catalysis of an Alcohol Dehydrogenase and Rhodium‐Modified Periodic Mesoporous Organosilica

• Published in: Angewandte Chemie International Edition Vol. 58; no. 27; pp. 9150 - 9154
• Main Authors: Himiyama, Tomoki, Waki, Minoru, Maegawa, Yoshifumi, Inagaki, Shinji
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.07.2019
• Edition: International ed. in English
• Subjects: Alcohol; Alcohol dehydrogenase; Alcohols; Amino acids; Bovine serum albumin; Catalysis; Catalysts; Catalytic activity; Coordination compounds; Deactivation; Dehydrogenase; Dehydrogenases; Enantiomers; enzyme catalysis; Enzymes; heterogeneous catalysis; Hydrogenation; Inactivation; mesoporous materials; Metal complexes; NAD; NADH; Nicotinamide adenine dinucleotide; Rhodium; Serum albumin; enzyme catalysis; heterogeneous catalysis; hydrogenation; mesoporous materials; rhodium
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201904116

The combined use of a metal‐complex catalyst and an enzyme is attractive, but typically results in mutual inactivation. A rhodium (Rh) complex immobilized in a bipyridine‐based periodic mesoporous organosilica (BPy‐PMO) shows high catalytic activity during transfer hydrogenation, even in the presence of bovine serum albumin (BSA), while a homogeneous Rh complex exhibits reduced activity due to direct interaction with BSA. The use of a smaller protein or an amino acid revealed a clear size‐sieving effect of the BPy‐PMO that protected the Rh catalyst from direct interactions. A combination of Rh‐immobilized BPy‐PMO and an enzyme (horse liver alcohol dehydrogenase; HLADH) promoted sequential reactions involving the transfer hydrogenation of NAD+ to give NADH followed by the asymmetric hydrogenation of 4‐phenyl‐2‐butanone with high enantioselectivity. The use of BPy‐PMO as a support for metal complexes could be applied to other systems consisting of a metal‐complex catalyst and an enzyme. A rhodium complex immobilized in a bipyridine‐based periodic mesoporous organosilica, Rh@PMO, exhibited high catalytic activity during transfer hydrogenation, even in the presence of a protein, indicating excellent tolerance for the protein due to the size‐sieving effect of the PMO. A mixture of Rh@PMO and an alcohol dehydrogenase promoted sequential reactions to afford an enantiomeric product with high conversion and enantioselectivity.