Ruthenium-carbon

An initial addition of a ruthenium-oxygen double bond to a a-C—H bond leads to an intermediate containing a carbon-ruthenium bond. This bond suffers a homolytic scission leading to a carbon radical, which is oxidized to a carbocation that provides a carbonyl group by deprotonation. 

HYDROGENATION CATALYSTS Bis-(pyridine)dimethylformamidcdichlororbo-dium borohydride. Iron pentacarbonyl. Lindlar catalyst. Nickel boride. Palladium-on-calcium carbonate. Rhodium-on-alumina. Rhodium-on-carbon. Ruthenium trichloride hydrate. Triton dodecacar-bonyL Tris(tiiplienylpho ine)chloto-... 

LS counters are suitable for measuring radionuclides that emit only very low-energy beta particles or electrons, notably tritium (Emax = 18.6 keV). When tritium is measured as tritiated water and its activity is reported relative to water weight or volume, no yield measurement is needed. Liquid samples, e.g., water from the environment, process streams, urine, or dissolved solids, can be counted directly or purified by distillation. Results for purified samples are more reliable to the extent that the radioelement can be identified, quenching is stabilized, and luminescent contaminants are removed. Reagents may have to be added to the distillation flask to hold back other potentially volatile radionuclides, such as radioactive iodine, carbon, ruthenium, or technetium. 

Algharaibeh, Z., X. R. Liu, and P. G. Pickup. 2009. An asymmetric anthraquinone-modified carbon/ruthenium oxide supercapacitor. Journal of Power Sources 187 640-643. 

C. Lin, J. A. Ritter, and B. N. Popov, Development of Carbon-Metal Oxide Supercapacitors from Sol-Gel Derived Carbon-Ruthenium Xerogels, J. Electrochem. Soc., 146, pp. 3155-60, 1999. 

Hu C-C, Wang C-C (2002) Improving the utilization of ruthenium oxide within thick carbon-ruthenium oxide composites by annealing and anodizing for electrochemical supercapacitors. Electrochem Commun 4 554-559... 

A different course of events is followed by diynes in the presence of a ruthenium catalyst and water (Scheme 11.88). 2i The mechanism is believed to involve the formation of a ruthenacyclopentadiene 11.268, which is attacked by water at the less-hindered position. Break-up of the ruthenacycle and protonolysis of the carbon-ruthenium bond delivers the product 11.267. 

Hartwig JF, Bergman RG, Andersen RA (1991) Insertion reactions of CO and CO2 with ruthenium benzyl, arylamido, and aryloxide complexes a comparison of the reactivity of ruthenium-carbon, ruthenium-nitrogen, and ruthenium-oxygen bonds. J Am Chem Soc 113 6499-6508... 

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