Effects of molecular nitrogen on coordination-metal catalysis *1I. Inhibiting influence of dinitrogen on the isomerization of 1-pentene catalyzed by dihydrido(dinitrogen)tris(triphenylphosphine)ruthenium

The isomerization of 1-pentene is catalyzed by RuH2(N2)(PPh3), in toluene at 25 °C. The reaction shows two distinct stages: it proceeds very rapidly initially and is accompanied by formation of 1 mole of pentane per mole of catalyst; then the rate quickly declines and the reaction follows first order kinetics. In both stages the isomerization is retarded by the addition of N2. The kinetic data suggest that the catalytically active species are RuH2(PPh3)3 in the first stage of the isomerization and Ru(PPh3)3 in the second stage. The inhibiting effects of N2 are attributed to the ability of N2 to compete with the olefin for coordination to the metal. Infrared and NMR spectroscopic data lend support to this conclusion.