Abstract
The reduction reaction of the Cu(II)-pitn complex (pitn = 1,3-di(pyridine-2-carboxaldimino)propane) by decamethylferrocene [Fe(Cp*)2] was examined in acetonitrile. The observed pseudo-first-order rate constants exhibited saturation kinetics with increasing excess amount of [Fe(Cp*)2]. Detailed analyses revealed that the reaction is controlled by a structural change prior to the electron transfer step, rather than a conventional bimolecular electron transfer process preceded by ion pair (encounter complex) formation. The rate constant for the structural change was estimated to be 275 ± 13 s-1 at 298 K ({increment}H* = 33.3 ± 1.0 kJ·mol-1, {increment}S* = 86 ± 5 J·mol-1·K-1), which is the fastest among gated reactions involving CuN4 complexes. It was confirmed by EPR measurement and Conflex calculations that the dihedral angle between the two N-N planes is significantly large (40°) in solution whereas it is merely 17.14° in the crystal.
| Original language | English |
|---|---|
| Journal | Journal of Solution Chemistry |
| DOIs | |
| Publication status | Accepted/In press - 2014 Apr 5 |
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Keywords
- Acetonitrile
- Cu(II)(pitn)
- Cyclic voltammetry
- Decemethylferrocene
- Rate constants
ASJC Scopus subject areas
- Molecular Biology
- Biophysics
- Biochemistry
- Physical and Theoretical Chemistry
Cite this
Reduction Reaction of the Copper(II) Complex Bearing 1,3-Di(pyridine-2-carboxaldimino)propane (pitn) by Decamethylferrocene in Acetonitrile. / Yamada, Atsutoshi; Watanabe, Yuki; Noda, Kyoko; Itoh, Sumitaka; Ishihara, Koji; Inamo, Masahiko; Hassan, Refat Moustafa; Takagi, Hideo D.
In: Journal of Solution Chemistry, 05.04.2014.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Reduction Reaction of the Copper(II) Complex Bearing 1,3-Di(pyridine-2-carboxaldimino)propane (pitn) by Decamethylferrocene in Acetonitrile
AU - Yamada, Atsutoshi
AU - Watanabe, Yuki
AU - Noda, Kyoko
AU - Itoh, Sumitaka
AU - Ishihara, Koji
AU - Inamo, Masahiko
AU - Hassan, Refat Moustafa
AU - Takagi, Hideo D.
PY - 2014/4/5
Y1 - 2014/4/5
N2 - The reduction reaction of the Cu(II)-pitn complex (pitn = 1,3-di(pyridine-2-carboxaldimino)propane) by decamethylferrocene [Fe(Cp*)2] was examined in acetonitrile. The observed pseudo-first-order rate constants exhibited saturation kinetics with increasing excess amount of [Fe(Cp*)2]. Detailed analyses revealed that the reaction is controlled by a structural change prior to the electron transfer step, rather than a conventional bimolecular electron transfer process preceded by ion pair (encounter complex) formation. The rate constant for the structural change was estimated to be 275 ± 13 s-1 at 298 K ({increment}H* = 33.3 ± 1.0 kJ·mol-1, {increment}S* = 86 ± 5 J·mol-1·K-1), which is the fastest among gated reactions involving CuN4 complexes. It was confirmed by EPR measurement and Conflex calculations that the dihedral angle between the two N-N planes is significantly large (40°) in solution whereas it is merely 17.14° in the crystal.
AB - The reduction reaction of the Cu(II)-pitn complex (pitn = 1,3-di(pyridine-2-carboxaldimino)propane) by decamethylferrocene [Fe(Cp*)2] was examined in acetonitrile. The observed pseudo-first-order rate constants exhibited saturation kinetics with increasing excess amount of [Fe(Cp*)2]. Detailed analyses revealed that the reaction is controlled by a structural change prior to the electron transfer step, rather than a conventional bimolecular electron transfer process preceded by ion pair (encounter complex) formation. The rate constant for the structural change was estimated to be 275 ± 13 s-1 at 298 K ({increment}H* = 33.3 ± 1.0 kJ·mol-1, {increment}S* = 86 ± 5 J·mol-1·K-1), which is the fastest among gated reactions involving CuN4 complexes. It was confirmed by EPR measurement and Conflex calculations that the dihedral angle between the two N-N planes is significantly large (40°) in solution whereas it is merely 17.14° in the crystal.
KW - Acetonitrile
KW - Cu(II)(pitn)
KW - Cyclic voltammetry
KW - Decemethylferrocene
KW - Rate constants
UR - http://www.scopus.com/inward/record.url?scp=84897346710&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84897346710&partnerID=8YFLogxK
U2 - 10.1007/s10953-014-0154-7
DO - 10.1007/s10953-014-0154-7
M3 - Article
AN - SCOPUS:84897346710
JO - Journal of Solution Chemistry
JF - Journal of Solution Chemistry
SN - 0095-9782
ER -