2,2'-Azobis(pyridine) (abpy) as a multiply reducible tetradentate ligand. EPR evidence for the configurational dependence of intramolecular electron transfer in the stereoisomeric tris-chelate ruthenium complexes Ru(abpy)n(bpy)3-nm (n = 2, 3; m = 2+ to 3-)
Fac- and mer-Ru(abpy)32+ (abpy = 2,2'-azobis(pyridine) and 2 out of the 3 possible diastereoisomers of Ru(abpy)2(bpy)2+ were isolated via HPLC and identified by their 1H NMR spectra. Electrochem. potentials for several 1-electron redn. steps and UV/visible spectroelectrochem. features vary to a small but detectable degree for the resp. pairs of isomers. The absence of a room-temp. EPR signal for 1 of the 2 isolated isomers of RuII(abpy-)(abpy)(bpy).bul.+ demonstrates the structural requirements for intramol. electron transfer. A 99,101Ru EPR hyperfine coupling of $\sim$0.8 mT was established for the previously reported radical ion Ru(abpy)(bpy)2.bul.+. The free a-azimino chelate is in mononuclear complexes of abpy render these systems suitable for the construction of polynuclear compds. The exceptional p-acceptor capability of abpy is illustrated by the reversible acceptance of $\geq$8 electrons by (Ru(bpy)22(μ,η4-abpy)n. on SciFinder(R)
%0 Journal Article
%1 Krejcik.1993
%A Krejcik, Michael
%A Zalis, Stanislav
%A Klima, Jiri
%A Sykora, David
%A Matheis, Walter
%A Klein, Axel
%A Kaim, Wolfgang.
%D 1993
%J Inorganic Chemistry
%K azabispyridine bipyridine electrochem isomer isomer;electronic redn ruthenium spectra
%N 15
%P 3362--3368
%R 10.1021/ic00067a029
%T 2,2'-Azobis(pyridine) (abpy) as a multiply reducible tetradentate ligand. EPR evidence for the configurational dependence of intramolecular electron transfer in the stereoisomeric tris-chelate ruthenium complexes Ru(abpy)n(bpy)3-nm (n = 2, 3; m = 2+ to 3-)
%V 32
%X Fac- and mer-Ru(abpy)32+ (abpy = 2,2'-azobis(pyridine) and 2 out of the 3 possible diastereoisomers of Ru(abpy)2(bpy)2+ were isolated via HPLC and identified by their 1H NMR spectra. Electrochem. potentials for several 1-electron redn. steps and UV/visible spectroelectrochem. features vary to a small but detectable degree for the resp. pairs of isomers. The absence of a room-temp. EPR signal for 1 of the 2 isolated isomers of RuII(abpy-)(abpy)(bpy).bul.+ demonstrates the structural requirements for intramol. electron transfer. A 99,101Ru EPR hyperfine coupling of $\sim$0.8 mT was established for the previously reported radical ion Ru(abpy)(bpy)2.bul.+. The free a-azimino chelate is in mononuclear complexes of abpy render these systems suitable for the construction of polynuclear compds. The exceptional p-acceptor capability of abpy is illustrated by the reversible acceptance of $\geq$8 electrons by (Ru(bpy)22(μ,η4-abpy)n. on SciFinder(R)
@article{Krejcik.1993,
abstract = {Fac- and mer-[Ru(abpy)3]2+ (abpy = 2,2'-azobis(pyridine) and 2 out of the 3 possible diastereoisomers of [Ru(abpy)2(bpy)]2+ were isolated via HPLC and identified by their 1H NMR spectra. Electrochem. potentials for several 1-electron redn. steps and UV/visible spectroelectrochem. features vary to a small but detectable degree for the resp. pairs of isomers. The absence of a room-temp. EPR signal for 1 of the 2 isolated isomers of [RuII(abpy-)(abpy)(bpy)].bul.+ demonstrates the structural requirements for intramol. electron transfer. A 99,101Ru EPR hyperfine coupling of $\sim$0.8 mT was established for the previously reported radical ion [Ru(abpy)(bpy)2].bul.+. The free \textgreek{a}-azimino chelate is in mononuclear complexes of abpy render these systems suitable for the construction of polynuclear compds. The exceptional \textgreek{p}-acceptor capability of abpy is illustrated by the reversible acceptance of $\geq$8 electrons by {[(Ru(bpy)2]2(μ,η4-abpy)}n. [on SciFinder(R)]},
added-at = {2019-07-15T13:41:23.000+0200},
author = {Krejcik, Michael and Zalis, Stanislav and Klima, Jiri and Sykora, David and Matheis, Walter and Klein, Axel and Kaim, Wolfgang.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2312cc76c16ed3d77cf119eef8e253192/b_schwederski},
doi = {10.1021/ic00067a029},
interhash = {5836afeb600585598041b0ef66f14bbe},
intrahash = {312cc76c16ed3d77cf119eef8e253192},
issn = {0020-1669},
journal = {Inorganic Chemistry},
keywords = {azabispyridine bipyridine electrochem isomer isomer;electronic redn ruthenium spectra},
number = 15,
pages = {3362--3368},
timestamp = {2019-07-15T11:42:10.000+0200},
title = {2,2'-Azobis(pyridine) (abpy) as a multiply reducible tetradentate ligand. EPR evidence for the configurational dependence of intramolecular electron transfer in the stereoisomeric tris-chelate ruthenium complexes [Ru(abpy)n(bpy)3-n]m (n = 2, 3; m = 2+ to 3-)},
volume = 32,
year = 1993
}