The redox systems [(NC)5Fe(m-L)Fe(CN)5]6-/5-/4- with L = pyrazine (1n), 4,4'-bipyridine (2n) or 1,2-bis(4-pyridyl)ethene (3n), and [(NC)4Fe(m-bmtz)Fe(CN)4]5-/4-/3- (4n) with bmtz = 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine were studied in MeCN and other aprotic solvents. The comproportionation consts. Kc for the mixed-valent diiron(III, II) intermediates vary from \textless10 for 35- via 106.5 for 15- to 1014.1 for 43-. Intervalence charge transfer band maxima lie between 1270 nm (25-) and 2475 nm (15-). In comparison with previous results from aq. solns., the system 1n in particular shows increased metal-metal interaction. UV-visible and IR spectroelectrochem. suggest a localized/delocalized borderline situation for 15- in MeCN, with only slightly weaker metal-metal coupling than in the related Creutz-Taube ion. The established strong solvent sensitivity of cyanoiron complexes can be exploited in mixed-valence chem. [on SciFinder(R)]
%0 Journal Article
%1 Ketterle.1999
%A Ketterle, Michael
%A Kaim, Wolfgang
%A Olabe, Jose A.
%A Parise, Alejandro R.
%A Fiedler, Jan.
%D 1999
%J Inorganica Chimica Acta
%K ESR IR UV bipyridine comproportionation const;mixed cyano electrochem iron prepn pyrazine pyridylethene pyrimidyltetrazine pyrimidyltetrazine;iron pyrimidyltetrazine;pyrazine redox redox;electrochem redox;pyridylethene redox;pyrimidyltetrazine valence
%N 1-2
%P 66--73
%R 10.1016/S0020-1693(99)00039-0
%T Widely differing stabilities of molecule-bridged cyanodiiron(III,II) species in non-aqueous solvents
%V 291
%X The redox systems [(NC)5Fe(m-L)Fe(CN)5]6-/5-/4- with L = pyrazine (1n), 4,4'-bipyridine (2n) or 1,2-bis(4-pyridyl)ethene (3n), and [(NC)4Fe(m-bmtz)Fe(CN)4]5-/4-/3- (4n) with bmtz = 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine were studied in MeCN and other aprotic solvents. The comproportionation consts. Kc for the mixed-valent diiron(III, II) intermediates vary from \textless10 for 35- via 106.5 for 15- to 1014.1 for 43-. Intervalence charge transfer band maxima lie between 1270 nm (25-) and 2475 nm (15-). In comparison with previous results from aq. solns., the system 1n in particular shows increased metal-metal interaction. UV-visible and IR spectroelectrochem. suggest a localized/delocalized borderline situation for 15- in MeCN, with only slightly weaker metal-metal coupling than in the related Creutz-Taube ion. The established strong solvent sensitivity of cyanoiron complexes can be exploited in mixed-valence chem. [on SciFinder(R)]
@article{Ketterle.1999,
abstract = {The redox systems [(NC)5Fe(\textgreek{m}-L)Fe(CN)5]6-/5-/4- with L = pyrazine (1n), 4,4'-bipyridine (2n) or 1,2-bis(4-pyridyl)ethene (3n), and [(NC)4Fe(\textgreek{m}-bmtz)Fe(CN)4]5-/4-/3- (4n) with bmtz = 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine were studied in MeCN and other aprotic solvents. The comproportionation consts. Kc for the mixed-valent diiron(III, II) intermediates vary from {\textless}10 for 35- via 106.5 for 15- to 1014.1 for 43-. Intervalence charge transfer band maxima lie between 1270 nm (25-) and 2475 nm (15-). In comparison with previous results from aq. solns., the system 1n in particular shows increased metal-metal interaction. UV-visible and IR spectroelectrochem. suggest a localized/delocalized borderline situation for 15- in MeCN, with only slightly weaker metal-metal coupling than in the related Creutz-Taube ion. The established strong solvent sensitivity of cyanoiron complexes can be exploited in mixed-valence chem. [on SciFinder(R)]},
added-at = {2022-06-15T11:26:56.000+0200},
author = {Ketterle, Michael and Kaim, Wolfgang and Olabe, Jose A. and Parise, Alejandro R. and Fiedler, Jan.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2c465ecb2e796de0eae02a03cd2563bba/huebleriac},
doi = {10.1016/S0020-1693(99)00039-0},
interhash = {1c0d89a65c0c19c8fb69eb8a641860fd},
intrahash = {c465ecb2e796de0eae02a03cd2563bba},
issn = {0020-1693},
journal = {Inorganica Chimica Acta},
keywords = {ESR IR UV bipyridine comproportionation const;mixed cyano electrochem iron prepn pyrazine pyridylethene pyrimidyltetrazine pyrimidyltetrazine;iron pyrimidyltetrazine;pyrazine redox redox;electrochem redox;pyridylethene redox;pyrimidyltetrazine valence},
number = {1-2},
pages = {66--73},
timestamp = {2022-06-15T09:26:56.000+0200},
title = {Widely differing stabilities of molecule-bridged cyanodiiron(III,II) species in non-aqueous solvents},
volume = 291,
year = 1999
}
