TY - JOUR
T1 - Switching the Mechanism of NADH Photooxidation by Supramolecular Interactions
AU - Mengele, Alexander Klaus
AU - Weixler, Dominik
AU - Chettri, Avinash
AU - Maurer, Maite
AU - Huber, Fabian Lukas
AU - Seibold, Gerd Michael
AU - Dietzek, Benjamin
AU - Eikmanns, Bernhard Johannes
AU - Rau, Sven
PY - 2021
Y1 - 2021
N2 - A series of three Ru(II) polypyridine complexes was investigated for the selective photocatalytic oxidation of NAD(P)H to NAD(P)+ in water. A combination of (time-resolved) spectroscopic studies and photocatalysis experiments revealed that ligand design can be used to control the mechanism of the photooxidation: For prototypical Ru(II) complexes a 1O2 pathway was found. Rudppz ([(tbbpy)2Ru(dppz)]Cl2, tbbpy = 4,4´-di-tert-butyl-2,2´-bipyridine, dppz = dipyrido[3,2-a:2′,3′-c]phenazine), instead, initiated the cofactor oxidation by electron transfer from NAD(P)H enabled by supramolecular binding between substrate and catalyst. Expulsion of the photoproduct NAD(P)+ from the supramolecular binding site in Rudppz allowed very efficient turnover. Therefore, Rudppz permits repetitive selective assembly and oxidative conversion of reduced naturally occurring nicotinamides by recognizing the redox state of the cofactor under formation of H2O2 as additional product. This photocatalytic process can fuel discontinuous photobiocatalysis.
AB - A series of three Ru(II) polypyridine complexes was investigated for the selective photocatalytic oxidation of NAD(P)H to NAD(P)+ in water. A combination of (time-resolved) spectroscopic studies and photocatalysis experiments revealed that ligand design can be used to control the mechanism of the photooxidation: For prototypical Ru(II) complexes a 1O2 pathway was found. Rudppz ([(tbbpy)2Ru(dppz)]Cl2, tbbpy = 4,4´-di-tert-butyl-2,2´-bipyridine, dppz = dipyrido[3,2-a:2′,3′-c]phenazine), instead, initiated the cofactor oxidation by electron transfer from NAD(P)H enabled by supramolecular binding between substrate and catalyst. Expulsion of the photoproduct NAD(P)+ from the supramolecular binding site in Rudppz allowed very efficient turnover. Therefore, Rudppz permits repetitive selective assembly and oxidative conversion of reduced naturally occurring nicotinamides by recognizing the redox state of the cofactor under formation of H2O2 as additional product. This photocatalytic process can fuel discontinuous photobiocatalysis.
KW - Cofactors
KW - Photooxidation
KW - Ruthenium
KW - Singlet oxygen
KW - Supramolecular chemistry
U2 - 10.1002/chem.202103029
DO - 10.1002/chem.202103029
M3 - Journal article
C2 - 34547151
SN - 0947-6539
VL - 27
SP - 16840
EP - 16845
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 68
ER -