TY - JOUR
T1 - Oxygen atom transfer from a trans-Dioxoruthenium(VI) complex to nitric oxide
AU - Man, Wai Lun
AU - W.y. Lam, William
AU - Ng, Siu Mui
AU - Tsang, Wenny Y.K.
AU - Lau, Tai Chu
PY - 2012/1/2
Y1 - 2012/1/2
N2 - In aqueous acidic solutions trans-[RuVI(L)(O)2] 2+ (L=1,12-dimethyl-3,4:9,10-dibenzo-1,12-diaza-5,8- dioxacyclopentadecane) is rapidly reduced by excess NO to give trans-[Ru(L)(NO)(OH)]2+. When ≤1 mol equiv NO is used, the intermediate RuIV species, trans-[RuIV species, trans-RuIV(L)(O)(OH2)]2+ be detected. The reaction of RuIV(L)(O)(OH2)]2+ with NO is first order with respect to [RuIV] and [NO], k2=4.13 ± 0.21) × 101M-1s-1 at 298.0K. δH+ and δ S+ are (12.0 ±0.3)kcal mol-1 and -(11 ±1)calmol-1K-1, respectively. In CH3CN,δH+ andδS+ have the same values as in H2O; this suggests that the mechanism is the same in both solvents. In CH3CN, the reaction of [Ru VI(L)(O)2]2+ with NO produces a blue-green species with λmax at approximately 650nm, which is characteristic of N2O3. N2O3 is formed by coupling of NO2 with excess NO; it is relatively stable in CH3CN, but undergoes rapid hydrolysis in H2O. A mechanism that involves oxygen atom transfer from [RuVI(L)(O)2] 2+ to NO to produce NO2 is proposed. The kinetics of the reaction of [RuIV(L)(O)(OH2)]2+ with NO has also been investigated. In this case, the data are consistent with initial one-electron O- transfer from RuIV to NO to produce the nitrito species [RuIII(L)(ONO)(OH2)]2+ (k 2>106M-1s-1), followed by a reaction with another molecule of NO to give [Ru(L)(NO)(OH)]2+ and NO2- (k2=54.7M-1s-1).
AB - In aqueous acidic solutions trans-[RuVI(L)(O)2] 2+ (L=1,12-dimethyl-3,4:9,10-dibenzo-1,12-diaza-5,8- dioxacyclopentadecane) is rapidly reduced by excess NO to give trans-[Ru(L)(NO)(OH)]2+. When ≤1 mol equiv NO is used, the intermediate RuIV species, trans-[RuIV species, trans-RuIV(L)(O)(OH2)]2+ be detected. The reaction of RuIV(L)(O)(OH2)]2+ with NO is first order with respect to [RuIV] and [NO], k2=4.13 ± 0.21) × 101M-1s-1 at 298.0K. δH+ and δ S+ are (12.0 ±0.3)kcal mol-1 and -(11 ±1)calmol-1K-1, respectively. In CH3CN,δH+ andδS+ have the same values as in H2O; this suggests that the mechanism is the same in both solvents. In CH3CN, the reaction of [Ru VI(L)(O)2]2+ with NO produces a blue-green species with λmax at approximately 650nm, which is characteristic of N2O3. N2O3 is formed by coupling of NO2 with excess NO; it is relatively stable in CH3CN, but undergoes rapid hydrolysis in H2O. A mechanism that involves oxygen atom transfer from [RuVI(L)(O)2] 2+ to NO to produce NO2 is proposed. The kinetics of the reaction of [RuIV(L)(O)(OH2)]2+ with NO has also been investigated. In this case, the data are consistent with initial one-electron O- transfer from RuIV to NO to produce the nitrito species [RuIII(L)(ONO)(OH2)]2+ (k 2>106M-1s-1), followed by a reaction with another molecule of NO to give [Ru(L)(NO)(OH)]2+ and NO2- (k2=54.7M-1s-1).
KW - atom transfer
KW - kinetics
KW - nitric oxide
KW - oxygen
KW - ruthenium
UR - http://www.scopus.com/inward/record.url?scp=84555188423&partnerID=8YFLogxK
U2 - 10.1002/chem.201102297
DO - 10.1002/chem.201102297
M3 - Article
C2 - 22139634
AN - SCOPUS:84555188423
SN - 0947-6539
VL - 18
SP - 138
EP - 144
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
IS - 1
ER -