摘要:
The kinetics and mechanism of the reduction of trans-[RuIVL(O)(H2O)]2 to trans-(RuIIIL(OH)(H2O)]2+ (L = 6,7,8,9,10,11,17,18-octahydro-6,10-dimethyl-5H-dibenzo[e,n][1,4,8,12]dioxadiazacyclo-pentadecine) in aqueous solution by cis-[Ru(II)(NH3)4(isn)2]2+ (isn = isonicotinamide) and of trans-[RuIIIL(OH)(H2O)]2+ to trans-[RuIIL(H2O)2]2+ by [Ru(II)(NH3)4(bipy]2+ (bipy = 2,2'-bipyridine) have been studied. The reactive intermediates are trans-[RuIVL(OH)(H2O)]3+ and trans-[RuIIIL(H2O)2]3+ respectively. The rate constants k(e1) and k(e2) for the reduction of trans-[RuIVL(OH)(H2O)]3+ and trans-[RuIIIL(H2O)2]3+ have been obtained and can be correlated with the Marcus cross-relation. The estimated self-exchange rate constants of trans-[RuL(OH)(H2O)]3+/2+ and trans-[RuL(H2O)2]3+/2+ couples are 3.1 x 10(-4) and 3.9 x 10(3) dm3 mol-1 s-1 respectively. The complex trans-[RuIIIL(OH)(H2O)][ClO4]2 has been characterized by X-ray crystallography: space group P1BAR, a = 11.108(2), b = 11.683(1), c = 12.349(1) angstrom, alpha = 89.38(1), beta = 64.81(1), gamma = 71.44(1)-degrees and Z = 2.