Evolution of hydrogen upon the photolysis of deaerated solutions of alkylbis(acetylacetone)ethylenediiminecobalt(III)

Journal Article · Thu Jan 01 04:00:00 EST 1987 · Sov. J. Coordinat. Chem.; (United States)

OSTI ID:6449198

Ortigosa, K; Shagisultanova, G A

The results of an investigation of the photochemical reactions taking place in deaerated solutions of pentacoordinate cobalt complexes with the general formula (RCo/sup III/(bae)), where R = CH/sub 3/, C/sub 3/H/sub 7/, C/sub 4/H/sub 9/, and i-C/sub 4/H/sub 9/, and bae stands for bis(acetylacetone)ethylenediimine, have been presented. The influence of the concentration and pH of the solutions, the nature of the alkyl radical, the nature of the solvent, and an addition of the solvent to an irradiated solution, as well as the intensity and energy of the exciting ligand, on the yield of hydrogen has been investigated. It has been shown that the important factors influencing the efficiency of the evolution of hydrogen are the concentration of the solution and the nature of the solvent. It has been found that, depending on the photolysis conditions, the yield of hydrogen in alcoholic solutions reaches values greater than 10 moles per mole of the complex. The photolysis of the complexes (RCo/sup III/(Bae)) in deaerated alcoholic solutions has been studied by ESR at 77/sup 0/K. The spectra of the photolytic products contain a signal from a low-spin cobalt-(II) complex with the formula (Co/sup II/(bae)) and signals which belong to the radicals of the corresponding alcohols. The mechanism of the radical chain photochemical reactions of the complexes (RCo/sup III/(bae)) in deaerated liquid alcoholic solutions has been presented. The analysis of the results allows the formation of a cobalt(I) complex in the catalytic cycle.

• Research Organization: A.I. Gertsen Leningrad State Pedagogic Institute, USSR
• OSTI ID: 6449198
• Journal Information: Sov. J. Coordinat. Chem.; (United States), Journal Name: Sov. J. Coordinat. Chem.; (United States) Vol. 12:3; ISSN SJCCD
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
080106* -- Hydrogen-- Production-- Biosynthesis & Photochemical Processes
ACETYLACETONE
ALCOHOLS
ALKENES
ANGULAR MOMENTUM
CATALYSTS
CATALYTIC EFFECTS
CHELATING AGENTS
CHEMICAL REACTION KINETICS
CHEMICAL REACTION YIELD
CHEMICAL REACTIONS
COBALT COMPLEXES
COMPARATIVE EVALUATIONS
COMPLEXES
DECOMPOSITION
EFFICIENCY
ELECTRON SPIN RESONANCE
ELEMENTS
ETHANOL
ETHYLENE
HYDROCARBONS
HYDROGEN
HYDROGEN PRODUCTION
HYDROXY COMPOUNDS
IMINES
KETONES
KINETICS
MAGNETIC RESONANCE
MATHEMATICAL MODELS
METHANOL
NONMETALS
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
ORGANIC SOLVENTS
PARTICLE PROPERTIES
PHOTOCHEMICAL REACTIONS
PHOTOLYSIS
PROPANOLS
QUANTITY RATIO
REACTION KINETICS
REAGENTS
REDOX POTENTIAL
RESONANCE
SOLVENT PROPERTIES
SOLVENTS
SPIN
TRANSITION ELEMENT COMPLEXES
YIELDS