Electrochemical metalloporphyrin-catalyzed reduction of chlorite.
We measured the redox stoichiometry and rate constants for the electrochemical reduction of ClO(2)(-) at pH 7, catalyzed by a series of metalloporphyrins of Mn, Fe, and Co with different proximal and distal environments. A clean four-electron reduction was observed. The catalytic activity correlates well with that observed in reduction of H(2)O(2). The axial imidazole and/or a redox-active distal metal (Cu or Co) increases the turnover frequency in several compounds. The metalloporphyrins were inert to ClO(x)(-) (x = 3,4) and IO(3)(-) but catalyzed facile two-electron reduction of IO(4)(-); six-electron reduction of BrO(3)(-) was also observed.
Department of Chemistry, Stanford University, Stanford, CA 94305, USA.
James P
JP
Collman
Roman
R
Boulatov
Christopher J
CJ
Sunderland
Irina M
IM
Shiryaeva
Katja E
KE
Berg
D002384:Catalysis; D002712:Chlorides / Q000737:chemistry*; D004563:Electrochemistry; D007700:Kinetics; D008665:Metalloporphyrins / Q000737:chemistry*; D010084:Oxidation-Reduction
D002712:Chlorides; D008665:Metalloporphyrins; C001599:chlorite