Oxidation of cobalt(II) macrocycles by tris(bipyridyl)ruthenium(III) ions

Journal Article · Wed Jun 27 04:00:00 EDT 1990 · Inorganic Chemistry; (USA)

DOI:https://doi.org/10.1021/ic00338a018· OSTI ID:6518437

Lee, Shaoyung; Bakac, A; Espenson, J H ^[1]

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1. Iowa State Univ., Ames (USA)

The kinetics of the electron-transfer reactions between Ru(bpy){sub 3}{sup 3+} and selected Co(II) complexes were evaluated by laser flash photolysis. The cobalt(II) complexes investigated were (H{sub 2}O){sub 2}Co(N{sub 4}mac){sup 2+}, with N{sub 4}mac = (14)aneN{sub 4}, C-meso-Me{sub 6}(14)aneN{sub 4}, tim ((14)tetraeneN{sub 4}), (15)aneN{sub 4}, and tmc (1,4,8,11-tetramethylcyclam). The respective second-order rate constants at 25{degree}C, {mu} = 0.10 M, are 3.2 {times} 10{sup 7}, 7.8 {times} 10{sup 6}, 2.1 {times} 10{sup 7}, 1.7 {times} 10{sup 7}, and 6 {times} 10{sup 5} M{sup {minus}1} s{sup {minus}1}. The results have been evaluated for their agreement with the Marcus theory. The complex Co(tmc){sup 2+} also reacts with Ru(phen){sub 3}{sup 3+} (k = 1.0 {times} 10{sup 6} M{sup {minus}1} s{sup {minus}1}) and with Ru(4,7-Me{sub 2}phen){sub 3}{sup 3+} (k = 3.2 {times} 10{sup 4} M{sup {minus}1} s{sup {minus}1}). These cobalt(II) complexes also quench the emission of the excited-state complex {sup *}Cr(bpy){sub 3}{sup 3+}. Quenching occurs by electron transfer, except for Co(tmc){sup 2+}, which appears to react by energy transfer. 41 refs., 2 figs., 1 tab.

• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6518437
• Journal Information: Inorganic Chemistry; (USA), Journal Name: Inorganic Chemistry; (USA) Vol. 29:13; ISSN 0020-1669; ISSN INOCA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
AZINES
BIPYRIDINES
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
COBALT COMPLEXES
COMPLEXES
DATA
EXPERIMENTAL DATA
HETEROCYCLIC COMPOUNDS
INFORMATION
KINETICS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PYRIDINES
REACTION KINETICS
REDOX REACTIONS
RUTHENIUM COMPLEXES
TRANSITION ELEMENT COMPLEXES