Unexpected NO transfer reaction between trans-[Ru(II)(NO+)(NH3)4(L)]3+ and Fe(III) species: observation of a heterobimetallic NO-bridged intermediate.
Inorg Chem
; 53(9): 4475-81, 2014 May 05.
Article
in En
| MEDLINE
| ID: mdl-24738470
ABSTRACT
The reaction between trans-[Ru(II)(NO(+))(NH3)4(L)](3+), L = ImN, IsN, Nic, P(OMe)3, P(OEt)3, and P(OH)(OEt)2, and the Fe(III) species [Fe(III)(TPPS)], metmyoglobin, and hemoglobin was monitored by UV-vis, EPR, and electrochemical techniques (DPV, CV). No reaction was observed when L = ImN, IsN, Nic, and P(OH)(OEt)2. However, when L = P(OMe)3 and P(OEt)3, the reaction was quantitative and the products were trans-[Ru(III)(H2O)(NH3)4(P(OR)3)](3+) and [Fe(II)(NO(+))] species. Reaction kinetics data and DFT calculations suggest a two-step reaction mechanism with the initial formation of a bridged [Ru-(µNO)-Fe] intermediate, which was confirmed through electrochemical techniques (E(0)' = -0.47 V vs NHE). The calculated specific rate constant values for the reaction were in the ranges k1 = 1.1 to 7.7 L mol(-1) s(-1) and k2 = 2.4 × 10(-3) to 11.4 × 10(-3) s(-1) for L = P(OMe)3 and P(OEt)3. The oxidation of the ruthenium center (Ru(II) to Ru(III)) containing the nitrosonium ligand suggests that NO can act as an electron transfer bridge between the two metal centers.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ferric Compounds
/
Ruthenium Compounds
/
Nitric Oxide
Language:
En
Journal:
Inorg Chem
Year:
2014
Document type:
Article
Affiliation country: