52389-25-0Relevant articles and documents
An all-inorganic, stable, and highly active tetraruthenium homogeneous catalyst for water oxidation
Geletii, Yurii V.,Botar, Bogdan,Koegerler, Paul,Hillesheim, Daniel A.,Musaev, Djamaladdin G.,Hill, Craig L.
, p. 3896 - 3899 (2009/02/08)
(Chemical Equation Presented) Oxidation without organics: A tetraruthenium polyoxometalate (see picture; Ru blue, O red, Si yellow, W black) catalyzes the rapid oxidation of H2O to O2 in water at ambient temperature, and shows considerable stability under turnover conditions. The complex was characterized by several methods, including X-ray crystallography and cyclic voltammetry.
Migration reactivities of a-bonded ligands of organoiron and organocobalt porphyrins depending on different high oxidation states
Fukuzumi, Shunichi
, p. 5000 - 5006 (2008/10/08)
Migration reactivities of σ-bonded organo-iron and -cobalt porphyrins were examined as a function of the compound oxidation state. Migration rates were determined for both the one-electron and two-electron oxidized species produced in the electron-transfer oxidation with different oxidants in acetonitrile at 298 K. The investigated compounds are represented as [(OETPP)Fe(R)]n+, where n = 1 or 2, OETPP = the dianion of 2,3,7,8,12,13,-17,18-octaethyl-5,10,15,20-tetraphenylporphyrin, and R = C6H5, 3,5-C6F2H3, or C6F5, and as [(TPP)Co(R)]n+, where n = 1 or 2, TPP = the dianion of 5,10,15,20-tetraphenylporphyrin, and R = CH3 or C6H5. The rapid two-electron oxidation of (OETPP)FeIII(R) occurs with [Ru(bpy)3]3+ (bpy = 2,2′-bipyridine) to produce [(OETPP)-FeIV(R)]2+. The formation of this species is followed by a slow migration of the σ-bonded R group to a nitrogen of the porphyrin ring to give [(N-ROETPP)FeII]2+ and then by a rapid electron-transfer oxidation of the migrated product with [Ru(bpy)3]3+ to yield [(N-ROETPP)FeIII]3+ as a final product. When [Ru(bpy)3]3+ is replaced by a much weaker oxidant such as ferricenium ion, only the one-electron oxidation of (OETPP)Fe(R) occurs to produce [(OETPP)FeIV(R)]+. A migration of the R group also occurs in the one-electron oxidized porphyrin species, [(OETPP)FeIV(R)]+, to produce [(N-ROETPP)FeII]+, which is rapidly oxidized by ferricenium ion to yield [(N-ROETPP)FeIII]2+. The migration rate of the R group in [(OETPP)FeIV(R)]+ is about 104 times slower than the migration rate of the corresponding two-electron oxidized species, [(OETPP)FeIV(R)]2+. The migration rate of the σ-bonded ligand of [(TPP)CoIV(R)]+, produced by the one-electron oxidation of (TPP)CoIII(R) with [Fe-(phen)3]3+ (phen = 1,10-phenanthroline) is also about 104 times slower than the migration rate of the R group in the corresponding two-electron oxidized species, [(TPP)CoIV(R)]2+, which is produced by the two-electron oxidation with [Ru(bpy)3]3+. A comparison of the migration rates with the oxidation states of the porphyrins indicates that the migration occurs via an intramolecular electron transfer from the R group to the Fe(IV) or Co(IV) metal of the organometallic porphyrin.
Oxidative homolysis of organochromium macrocycles
Steffan, Carl R.,Espenson, James H.,Bakac, Andreja
, p. 1134 - 1137 (2008/10/08)
The complexes RCrL(H2O)2+ (R = alkyl, aralkyl; L = 1,4,8,12-tetraazacyclopentadecane) are oxidized by Ru(bpy)33+ and 2E Cr(bpy)33+. The one-electron oxidized species RCrL(H2O)3+ undergoes subsequent homolysis; the R. radicals so produced may react with certain metal complexes, or they dimerize, depending on conditions. The rate constants for the rate-controlling step, electron transfer from RCrL(H2O)2+ to Ru(bpy)33+ or *Cr(bpy)33+, were measured by laser flash photolysis for an extensive range of R groups. For Ru(bpy)33+, the rate constants range from 14.2 L mol-1 s-1 (R = CH3) to 1.05 × 109 (R = 4-CH3C6H4CH2); for *Cr(bpy)33+, the corresponding values are 2.8 × 106 and 1.55 × 109 L mol-1 s-1. In both series, the order of rate constants is methyl . are linear, in accord with the rate-controlling step being electron transfer.
