Cu(II)-nitroxyl radicals as catalytic galactose oxidase mimics.
Results from Hammett correlation studies and primary kinetic isotope effects for the CuCl-TEMPO catalysed aerobic benzyl alcohol oxidations are inconsistent with an oxoammonium based mechanism. We postulate a copper-mediated dehydrogenation mechanism, in which TEMPO regenerates the active Cu(II)-species. This mechanism is analogous to that observed for Galactose Oxidase and mimics thereof.
Dijksman
Arné
A
Laboratory for Biocatalysis and Organic Chemistry, Department of Biotechnology, Delft University of Technology, Julianalaan 136, 2628 BL Delft, The Netherlands.
Arends
Isabel W C E
IW
Sheldon
Roger A
RA
D000438:Alcohols / Q000737:chemistry; D000975:Antioxidants / Q000737:chemistry; D001592:Benzyl Alcohols / Q000737:chemistry; D002384:Catalysis; D002625:Chemistry, Organic / Q000379:methods*; D003300:Copper / Q000494:pharmacology; D003497:Cyclic N-Oxides / Q000737:chemistry; D005692:Galactose Oxidase / Q000737:chemistry*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007700:Kinetics; D008956:Models, Chemical; D009589:Nitrogen Oxides / Q000737:chemistry*; D014466:Ultraviolet Rays
D000438:Alcohols; D000975:Antioxidants; D001592:Benzyl Alcohols; D003497:Cyclic N-Oxides; D009589:Nitrogen Oxides; D003300:Copper; D006861:Hydrogen Peroxide; D005692:Galactose Oxidase; C039900:nitroxyl; C029892:cupric chloride; C003959:TEMPO