title: Type 1 copper site synthetic model complexes with increased redox potentials.
abstract: Reactions of NaSCPh(3) with (R(3)tacn)Cu(OTf)(2) (R is Me, iPr; tacn is 1,4,7-triazacyclononane; OTf is CF(3)SO(3)(-)) yield blue complexes identified as ((R(3)tacn)CuSCPh(3))(OTf) on the basis of UV-vis, resonance Raman, and electron paramagnetic resonance (EPR) spectroscopy and electrospray ionization mass spectrometry. These complexes exhibit spectroscopic properties typical of type 1 copper sites in proteins, including diagnostic Sπ → Cu(d(x(2)-y(2))) ligand-to-metal charge transfer transitions at approximately 610-630 nm and small A(||) values in EPR spectra of less than 100 × 10(-4) cm(-1). Cyclic voltammetry experiments revealed redox potentials for the complexes similar to those of several low-potential type 1 copper proteins (e.g., azurin, stellacyanin) and approximately 0.5 V higher than those of previously reported model compounds. Thus, the new complexes mimic key aspects of both the structure and the function of type 1 copper sites.
authors.affiliation: Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant St. SE, Minneapolis, MN 55455, USA.
authors.forename: Lei
authors.initials: L
authors.lastname: Yang
authors.forename: William B
authors.initials: WB
authors.lastname: Tolman
mesh_terms: D001400:Azurin / Q000737:chemistry; D001419:Bacteria / Q000737:chemistry; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D003300:Copper / Q000737:chemistry*; D008667:Metalloproteins / Q000737:chemistry; D010084:Oxidation-Reduction; D010940:Plant Proteins / Q000737:chemistry; D010944:Plants / Q000737:chemistry; D013057:Spectrum Analysis
chemical_list: D056831:Coordination Complexes; D008667:Metalloproteins; D010940:Plant Proteins; D001400:Azurin; C003343:stellacyanin protein, plant; D003300:Copper