%0 Journal Article %1 Chanda.2003 %A Chanda, Nripen %A Sarkar, Biprajit %A Fiedler, Jan %A Kaim, Wolfgang %A Lahiri, Goutam Kumar. %D 2003 %J Dalton Transactions %K complex complex;electrochem complex;luminescence complex;mixed complex;ruthenium comproportionation const dinuclear dipyridylamine mononuclear polypyridylpyrazine prepn ruthenium valence %N 18 %P 3550--3555 %R 10.1039/B306065A %T Synthesis and mixed valence aspects of [(L)ClRu2(m-tppz)]n+ incorporating 2,2'-dipyridylamine (L) as ancillary and 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) as bridging ligand %X The tppz-bridged diruthenium complex [(L)ClRuII2(m-tppz)](ClO4)2, [1](ClO4)2 tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine, L = 2,2'-dipyridylamine and its mononuclear counterpart [(L)ClRuII(tppz)]ClO4, [2](ClO4) were synthesized. The 380 mV sepn. between successive RuII/RuIII couples in [1]2+ leads to a comproportionation const. (Kc) of 2.7 $\times$ 106. Consequently, the RuIIRuIII species [1]3+ exhibits a rather narrow intervalence charge transfer band at 1700 nm, suggesting a class III mixed-valence state, the electronic coupling const. (Vab) is calcd. at 2940 cm-1. [1]3+ Displays a rhombic EPR spectrum at 4 K (g1 = 3.390, g2 = 2.278, g3 = 1.697), characteristic of Ru(iii) in a distorted octahedral environment. Both complexes show two successive tppz-based redn. processes [(tppz)0/-1 and (tppz)-1/-2]. The 1-electron reduced species [1]+ is a tppz radical anion species with an intense low-energy band at 1105 nm and an axial EPR signal at 4 K (g1 = 2.008, g2 = g3 = 1.994). [1]2+ And [2]+ exhibit moderately strong emissions at 740 nm and 668 nm, resp., in EtOH-MeOH glass at 77 K. [on SciFinder(R)]

@article{Chanda.2003, abstract = {The tppz-bridged diruthenium complex [{(L)ClRuII}2(\textgreek{m}-tppz)](ClO4)2, [1](ClO4)2 {tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine, L = 2,2'-dipyridylamine} and its mononuclear counterpart [(L)ClRuII(tppz)]ClO4, [2](ClO4) were synthesized. The 380 mV sepn. between successive RuII/RuIII couples in [1]2+ leads to a comproportionation const. (Kc) of 2.7 $\times$ 106. Consequently, the RuIIRuIII species [1]3+ exhibits a rather narrow intervalence charge transfer band at 1700 nm, suggesting a class III mixed-valence state, the electronic coupling const. (Vab) is calcd. at 2940 cm-1. [1]3+ Displays a rhombic EPR spectrum at 4 K (g1 = 3.390, g2 = 2.278, g3 = 1.697), characteristic of Ru(iii) in a distorted octahedral environment. Both complexes show two successive tppz-based redn. processes [(tppz)0/-1 and (tppz)-1/-2]. The 1-electron reduced species [1]+ is a tppz radical anion species with an intense low-energy band at 1105 nm and an axial EPR signal at 4 K (g1 = 2.008, g2 = g3 = 1.994). [1]2+ And [2]+ exhibit moderately strong emissions at 740 nm and 668 nm, resp., in EtOH-MeOH glass at 77 K. [on SciFinder(R)]}, added-at = {2022-06-15T11:26:56.000+0200}, author = {Chanda, Nripen and Sarkar, Biprajit and Fiedler, Jan and Kaim, Wolfgang and Lahiri, Goutam Kumar.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/277cf79c87db0ff4e4de08a72f9256ca7/huebleriac}, doi = {10.1039/B306065A}, interhash = {0f25f049be3dc8819941b22919e4fbf8}, intrahash = {77cf79c87db0ff4e4de08a72f9256ca7}, issn = {1477-9226}, journal = {Dalton Transactions}, keywords = {complex complex;electrochem complex;luminescence complex;mixed complex;ruthenium comproportionation const dinuclear dipyridylamine mononuclear polypyridylpyrazine prepn ruthenium valence}, number = 18, pages = {3550--3555}, timestamp = {2022-06-15T09:26:56.000+0200}, title = {Synthesis and mixed valence aspects of [{(L)ClRu}2(\textgreek{m}-tppz)]n+ incorporating 2,2'-dipyridylamine (L) as ancillary and 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz) as bridging ligand}, year = 2003 }