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7749094 
Journal Article 
REACTIONS OF [NI(1,4,7-TRIAZACYCLONONANE)2]3+/2+ WITH THE COMPONENTS OF NITROUS-ACID 
Demaine, MM; Stanbury, DM 
1991 
Yes 
Inorganic Chemistry
ISSN: 0020-1669
EISSN: 1520-510X 
30 
9 
2104-2109 
English 
WOS:A1991FK18000029 
The reactions of [Ni(tacn)2]3+ with some of the components of nitrous acid have been studied in aqueous solution at 25 °C. NO2- reacts to form [Ni(tacn)2]2+ and NO3; and the rate law is -d[Ni(tacn)23+]/dt = k[Ni(tacn)23+][N(III)]/(1 + [H+]/Ka) with k = 212 ± 7 M-1 s-1 and Ka = (9.6 ± 1.1) × 10-4 M at μ = 0.1 M (LiClO4). Electron transfer from NO2- to [Ni(tacn)2]3+ is proposed as the rate-limiting step. In 0.79 mM NO, [Ni(tacn)2]3+ reacts with the rate law -d[Ni(tacn)23+]/dt = k′[Ni(tacn)23+] + k″[Ni(tacn)23+]/[H+] where k′= (1.02 ± 0.06) × 10′3 s′1 and k″ = (1.36 ± 0.07) × 10-4 M s-1 at μ = 1.0 M (LiClO4). The k″ pathway leads to destruction of the complex, presumably through nitrosation of the N-deprotonated conjugate base form of the Ni(III) reactant. The k′ pathway is interpreted as an outer-sphere electron-transfer reaction between NO and [Ni(tacn)2]3+. © 1991, American Chemical Society. All rights reserved.