title: Multicopper models for the laccase active site: effect of nuclearity on electrocatalytic oxygen reduction.
abstract: Cu complexes of 2,2'-dipicolylamine (DPA) were prepared and tested as electrocatalysts for the oxygen reduction reaction (ORR). To study the effect of multinuclearity on the ORR, two Cu-DPA units were connected with a flexible linker, and a third metal-binding pocket was installed in the ligand framework. ORR onset potentials and the diffusion-limited current densities of di- and tricopper complexes of DPA derivatives were found to be comparable to those of the simpler Cu-DPA system. Electrochemical analyses, crystallographic data, and metal-substitution studies suggested that Cu complexes of DPA derivatives reacted with O2 via a binuclear intermolecular pathway but that the Cu center in the third binding site did not participate in the ORR process. This study highlights the viability of Cu-DPA complexes to mimic the T3-site of laccase, and serves as a guide for designing future laccase models.
authors: Department of Chemistry, University of Illinois at Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
authors: Edmund C M
authors: EC
authors: Tse
authors: David
authors: D
authors: Schilter
authors: Danielle L
authors: DL
authors: Gray
authors: Thomas B
authors: TB
authors: Rauchfuss
authors: Andrew A
authors: AA
authors: Gewirth
mesh_terms: D000588:Amines / Q000737:chemistry* / Q000378:metabolism; D002384:Catalysis; D020134:Catalytic Domain; D003300:Copper / Q000737:chemistry* / Q000378:metabolism; D055664:Electrochemical Techniques; D042845:Laccase / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry* / Q000378:metabolism; D010848:Picolinic Acids / Q000737:chemistry* / Q000378:metabolism
chemical_list: C501847:2,2'-dipicolylamine; D000588:Amines; D009942:Organometallic Compounds; D010848:Picolinic Acids; D003300:Copper; D042845:Laccase; D010100:Oxygen