The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine
The new ruthenium(II) complex ion [(NC)5Ru(μ-pz)Ru(CN)5]6- has been prepared and studied as the hexakis(tetraethylammonium) salt. Although spectroelectrochemical experiments in dichloromethane were affected by adsorption as they were in other solvents, the compound could be oxidized via two reversib...
Guardado en:
| Autores principales: | , |
|---|---|
| Publicado: |
2000
|
| Materias: | |
| Acceso en línea: | https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00201693_v300-302_n_p125_Scheiring http://hdl.handle.net/20.500.12110/paper_00201693_v300-302_n_p125_Scheiring |
| Aporte de: |
| id |
paper:paper_00201693_v300-302_n_p125_Scheiring |
|---|---|
| record_format |
dspace |
| spelling |
paper:paper_00201693_v300-302_n_p125_Scheiring2023-06-08T14:40:49Z The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine Olabe Iparraguirre, Jose Antonio Parise, Alejandro Rubén Cyano complexes Mixed-valence complexes Ruthenium complexes Spectroelectrochemistry pyrazine derivative ruthenium derivative article complex formation Czech Republic electrochemistry Germany molecular interaction oxidation reduction reaction The new ruthenium(II) complex ion [(NC)5Ru(μ-pz)Ru(CN)5]6- has been prepared and studied as the hexakis(tetraethylammonium) salt. Although spectroelectrochemical experiments in dichloromethane were affected by adsorption as they were in other solvents, the compound could be oxidized via two reversible one-electron steps with a mixed-valent pentaanionic intermediate. In comparison with the iron and osmium analogues, the system [(NC)5Ru(μ-pz)Ru(CN)5]5- is distinguished by less negative redox potentials, a smaller comproportionation constant K(c) of only 104.7, a very broad (Δv( 1/2 ) = 4200 cm-1) symmetrical IVCT band at 1760 nm (ε = 2600 M-1 cm-1) conforming with the Hush model for weakly coupled mixed-valent systems, the absence of an EPR signal even at 3.5 K and the appearance of infrared bands (CN, pyrazine ring vibrations) indicating localized valence on the time scale of 10-12 s. Together with the high MLCT energies these results suggest a weaker metal-pyrazine interaction for the ruthenium system in comparison with the Fe and Os analogues reported previously. In relation to the Creutz-Taube ion, the substitution of ammine ligands by non-innocent cyanide ions attenuates the metal-metal interaction across the π accepting pyrazine bridge. (C) 2000 Elsevier Science S.A. Fil:Olabe, J.A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. Fil:Parise, A.R. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina. 2000 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00201693_v300-302_n_p125_Scheiring http://hdl.handle.net/20.500.12110/paper_00201693_v300-302_n_p125_Scheiring |
| institution |
Universidad de Buenos Aires |
| institution_str |
I-28 |
| repository_str |
R-134 |
| collection |
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) |
| topic |
Cyano complexes Mixed-valence complexes Ruthenium complexes Spectroelectrochemistry pyrazine derivative ruthenium derivative article complex formation Czech Republic electrochemistry Germany molecular interaction oxidation reduction reaction |
| spellingShingle |
Cyano complexes Mixed-valence complexes Ruthenium complexes Spectroelectrochemistry pyrazine derivative ruthenium derivative article complex formation Czech Republic electrochemistry Germany molecular interaction oxidation reduction reaction Olabe Iparraguirre, Jose Antonio Parise, Alejandro Rubén The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine |
| topic_facet |
Cyano complexes Mixed-valence complexes Ruthenium complexes Spectroelectrochemistry pyrazine derivative ruthenium derivative article complex formation Czech Republic electrochemistry Germany molecular interaction oxidation reduction reaction |
| description |
The new ruthenium(II) complex ion [(NC)5Ru(μ-pz)Ru(CN)5]6- has been prepared and studied as the hexakis(tetraethylammonium) salt. Although spectroelectrochemical experiments in dichloromethane were affected by adsorption as they were in other solvents, the compound could be oxidized via two reversible one-electron steps with a mixed-valent pentaanionic intermediate. In comparison with the iron and osmium analogues, the system [(NC)5Ru(μ-pz)Ru(CN)5]5- is distinguished by less negative redox potentials, a smaller comproportionation constant K(c) of only 104.7, a very broad (Δv( 1/2 ) = 4200 cm-1) symmetrical IVCT band at 1760 nm (ε = 2600 M-1 cm-1) conforming with the Hush model for weakly coupled mixed-valent systems, the absence of an EPR signal even at 3.5 K and the appearance of infrared bands (CN, pyrazine ring vibrations) indicating localized valence on the time scale of 10-12 s. Together with the high MLCT energies these results suggest a weaker metal-pyrazine interaction for the ruthenium system in comparison with the Fe and Os analogues reported previously. In relation to the Creutz-Taube ion, the substitution of ammine ligands by non-innocent cyanide ions attenuates the metal-metal interaction across the π accepting pyrazine bridge. (C) 2000 Elsevier Science S.A. |
| author |
Olabe Iparraguirre, Jose Antonio Parise, Alejandro Rubén |
| author_facet |
Olabe Iparraguirre, Jose Antonio Parise, Alejandro Rubén |
| author_sort |
Olabe Iparraguirre, Jose Antonio |
| title |
The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine |
| title_short |
The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine |
| title_full |
The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine |
| title_fullStr |
The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine |
| title_full_unstemmed |
The valence-localized decacyanodiruthenium(III,II) analogue of the Creutz-Taube ion. Completing the full d5/d6 triad [(NC)5M(μ-pz)M(CN)5]5-, M = Fe,Ru,Os; pz = pyrazine |
| title_sort |
valence-localized decacyanodiruthenium(iii,ii) analogue of the creutz-taube ion. completing the full d5/d6 triad [(nc)5m(μ-pz)m(cn)5]5-, m = fe,ru,os; pz = pyrazine |
| publishDate |
2000 |
| url |
https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00201693_v300-302_n_p125_Scheiring http://hdl.handle.net/20.500.12110/paper_00201693_v300-302_n_p125_Scheiring |
| work_keys_str_mv |
AT olabeiparraguirrejoseantonio thevalencelocalizeddecacyanodirutheniumiiiiianalogueofthecreutztaubeioncompletingthefulld5d6triadnc5mmpzmcn55mferuospzpyrazine AT parisealejandroruben thevalencelocalizeddecacyanodirutheniumiiiiianalogueofthecreutztaubeioncompletingthefulld5d6triadnc5mmpzmcn55mferuospzpyrazine AT olabeiparraguirrejoseantonio valencelocalizeddecacyanodirutheniumiiiiianalogueofthecreutztaubeioncompletingthefulld5d6triadnc5mmpzmcn55mferuospzpyrazine AT parisealejandroruben valencelocalizeddecacyanodirutheniumiiiiianalogueofthecreutztaubeioncompletingthefulld5d6triadnc5mmpzmcn55mferuospzpyrazine |
| _version_ |
1768545357157892096 |