Ruthenium , 2,2 -bipyridine complex structure

Since the copper complexes, [Cu(NN)2]+ and [Cu(NN)(PR3)2]+ (NN = 1,10-phenanthroline, 2,2 -bipyridine, and their derivatives) were applied to stoichiometric and catalytic photoreduction of cobalt(III) complexes [8a,b,e,9a,d], one can expect to perform the asymmetric photoreduction system with the similar copper(l) complexes if the optically active center is introduced into the copper(I) complex. To construct such an asymmetric photoreaction system, we need chiral copper(I) complex. Copper complex, however, takes a four-coordinate structure. This means that the molecular asymmetry around the metal center cannot exist in the copper complex, unlike in six-coordinate octahedral ruthenium(II) complexes. Thus we need to synthesize some chiral ligand in the copper complexes. 

Compound 37 (Figure 10) forms a zs(2,2 -bipyridine)ruthenium(II) complex 38 [Ru(37)(bpy)2Cl2l. An X-ray crystal structure shows that it... 

Videla M, Jacinto JS et al (2006) New ruthenium nitrosyl complexes with tris(l-pyrazolyl) methane (tpm) and 2,2 -bipyridine (bpy) coligands. Structure, spectroscopy, and electrophilic and nucleophilic reactivities of bound nitrosyl. Inorg Chem 45 8608-8617... 

Arakawa, R., Matsuda, F, Matsubayashi, G., Matsuo, T. (1997) Structural Analysis of Photo-oxidized (Ethylenediamine)bis(2,2 -bipyridine)ruthenium(II) Complexes by Using On-line Electrospray Mass Spectrometry of Labeled Compounds. J. Am. Soc. Mass Spectrom. 8 713-717. 

It has been reported that tris(2,2 -bipyridine)ruthenium(II) chloride catalyzed the photooxidative polymerization of diaryl disulfides by O2, by which poly(thioarylene)s were efficiently prepared. The polymerization proceeded through the electrophilic reaction of the sulfonium cation which was produced selectively by the photoredox system. The ruthenium(II) complex provided the first photocatalytic system for the polymerization of diphenyl disulfide. The linear structures of the obtained polymers were confirmed (32). 

Rensmo H, Sodergren S, Patthey L, Westermark K, Vayssieres L, Kohle O, Briihwiler PA, Hagfeldt A, Siegbahn H (1997) The electrraiic structure of the c(s-bis(4,4 -dicarboxy-2, 2 -bipyridine)-bis(isothiocyanato)ruthenium(n) complex and its ligand 2,2 -bipyridyl-4, 4 -dicarboxylic acid studied with electron spectroscopy. Chem Phys Lett 274(l-3) 51-57... 

Polyamides and polyesters containing ruthenimn bipyridine complexes in their structures have been synthesized by Chan and coworkers." " Scheme 14 depicts the synthesis of polymer 64 by reaction of the metal-containing dicarboxylic acid complex 61 and the organic dicarboxylic acid (62) with an aromatic or aliphatic diamine (63). These polymers were thermally stable to temperatures between 320 and 500°C. Many of the polymers exhibited liquid crystalline characteristics. The photoconductivity of this class of polymer increased with increasing metal content." Chan also reported that polybenzo-bw-oxazoles and polybenzo-Z>w-thiazoles that contain ruthenium complexes coordinated to 2,2 bipyridyl units in the backbone... 

I. Yu., Grineva, L.G., Polishchuk, A.P., and Chernega, A.N., Products of quaternization of 4,4 -bipyridine with halogenated carboxylic acids. Synthesis, structure and photoreduction in the crystalline state, Russ. J. Gen. Chem., 68, 609, 1998 (d) Suzuki, M., Kimura, M., Hanabusa, K., and Shirai, H., Reversible color changes induced by photosensitized charge separation in partially quaternized poly(l-vinylimidazole)-bound ruthenium(ll) complex and viologen hlms, Eur. Polym. 

Complexation via amidinate units was found in ruthenium complexes containing tri- and pentacyclic trifluoromethylaryl-substituted quinoxalines. The complex fragment [(tbbpy)2Ru] (tbbpy = bis(4,4 -di-ferf-butyl-2,2 -bipyridine) has been employed in these compounds which have all been structurally characterized by X-ray diffraction. ... 

Scheme 3 shows the details of the synthetic strategy adopted for the preparation of heteroleptic cis- and trans-complexes. Reaction of dichloro(p-cymene)ruthenium(II) dimer in ethanol solution at reflux temperature with 4,4,-dicarboxy-2.2 -bipyridine (L) resulted the pure mononuclear complex [Ru(cymene)ClL]Cl. In this step, the coordination of substituted bipyridine ligand to the ruthenium center takes place with cleavage of the doubly chloride-bridged structure of the dimeric starting material. The presence of three pyridine proton environments in the NMR spectrum is consistent with the symmetry seen in the solid-state crystal structure (Figure 24). 

Amine-terminated, full-generation PAMAM and PPI dendrimers, as well as carboxylate-terminated half-generation PAMAM dendrimers, can directly bind metal ions to their surfaces via coordination to the amine or acid functionality. A partial hst of metal ions that have been bound to these dendrimers in this way includes Na+, K+, Cs+, Rb+, Fe +, Fe +, Gd +, Cu+, Cu +, Ag+, Mn +, Pd, Zn, Co, Rh+,Ru +,andPt + [18,19,27,36,54,82-96]. Tuxro et al.have also shown that the metal ion complexes, such as tris(2,2 -bipyridine)ruthenium (Rulbpylj), can be attached to PAMAM dendrimer surfaces by electrostatic attraction [97]. A wide variety of other famihes of dendrimers have also been prepared that bind metal ions to their periphery. These have recently been reviewed [3]. Such surface-bound metal ions can be used to probe dendrimer structure using optical spectroscopy, mass spectrometry, and electron paramagnetic resonance (EPR) [86-88,90,97-99]. 

Pyridine-based ligands which have been used for dendrimers are 2,2-bipyridine (bpy) 17,2,3-bis(2-pyridyl)pyrazine (2,3-dpp) 18 and its monomethylated salt 19, and 2,2 6, 2"-terpyridine 20. Their transition metal complexes possessing dendritic structures were first reported in the collaborative work of Denti, Campagne, and Balzani whose divergent synthetic strategy has led to systems containing 22 ruthenium centers. - The core unit is [Ru(2,3-dpp)3] 21 which contains three... 

The synthesis, crystal structure and electrochemical properties of a silver(l) coordination derivative of 2,3-dimethylthio-6-pyridyl tetrathiafulvalene <2007JCC2319> and ruthenium(n) polypyridine complexes [Ru(bpy)3- (TTF-dppz)4(PF6)2, (bpy = 2,2 -bipyridine dppz = 4, 5 -bis(propylthio)tetrathiafulvenyl[i]dipyr-ido[3,2-r 2, 3 -f]phenazine) <2007MI1504> were also investigated. 

Because bipyridines substituted at the 3 and 3 positions exhibit a large steric repulsion between substituents while in the cis configuration,27 they bind metals more weakly and form strained, nonplanar structures.28 However, a series of 3,3 -disubstituted bipyridines were coordinated to ruthenium, and it was demonstrated that molecular distortions could be used to advantage in modulating physical properties of the resulting complexes.29... 

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