2,2 -Bipyridine-3,3 -dicarboxylic acid

Bipyridine was first prepared in 1888 by the dry distillation of the copper salt of picolinic acid. This method and modifications give low yields of 2,2 -bipyridine. Another old method Involves oxidation of 1,10-phenanthrbline (28) to 2,2 -bipyridine-3,3 -dicarboxylic acid (29) by alkaline permanganate, followed by decarboxylation. This... 

The electrophilic reactions of co-ordinated 1,10-phenanthrolines are not always as simple as might be expected. Thus, the nitration of cobalt(m) 1,10-phenanthroline complexes yields 5-nitro-1,10-phenanthroline derivatives at low temperature, but prolonged reaction in hot solution leads to further reaction and oxidation of the ligand to give excellent yields of 1,10-phenanthroline-5,6-quinone complexes (Fig. 8-40). Even after the formation of the quinone, the complexes may exhibit further reaction. For example, reaction of the l,10-phenanthroline-5,6-quinone complexes with base results in the formation of a complex of 2,2 -bipyridine-3,3 -dicarboxylic acid (Fig. 8-41)... 

Trimethylene-2,2 -bipyridine-3,3 -dicarboxylic acid and l,l -tetra-methylene-2,2 -bipyridine-3,3 -dicarboxylic add atropisomers were baseline separated in 10 days on potato starch after tremendous effort to prepare the column. The authors stated that attempts to resolve theses acids were only successful with spedally conditioned columns of starch (95JPC14161). It is highly probable that more convenient chiral HPLC conditions are now available. 

Treatment of bipyridine-dicarboxylic acid 191 in alcohols with thionyl chloride and gaseous chlorine furnished the corresponding trichloroindolizines 193 through the intermediary of diesters 192 (Scheme 6) <2002J(P 1) 1688, 2002MI1, 2002MOL628>. 

The symmetrical bipyridine dicarboxylic acid was reported as a potent inhibitor of prolyl hydrolase, an enzyme involved in collagen biosynthesis (Fig. 16.16). The beneficial effect of drug duplication observed here may result of a single binding mode in each catalytic subunit. 

Reaction of -picoline over degassed Raney nickel was found to give 5,5 -dimethyl-2,2 -bipyridine (5), the structure of which was established by its synthesis from 2-bromo-5-methylpyridine. Oxidation of this dimethyl-2,2 -bipyridine, and similar oxidation of the diethyl-2,2 -bipyridine derived from 3-ethylpyridinc, gave the corresponding dicarboxylic acid and the same acid was produced by the action of degassed Raney nickel on sodium nicotinate (in water) or on ethyl nicotinate. These transformations established the 5,5 -substitution pattern for three 2,2 -bipyridines derived from 3-substituted pyridines but such evidence is not available for the biaryls... 

The most successful sensitizers so far tested are complexes of Ru(II) with various derivatives of 2,2 bipyridine, e.g. 2,2 -bipyridine 4,4 -dicarboxylic acid (L). The Ru(II)L3 complex is adsorbed from an aqueous solution of suitable pH value to oxidic semiconductors via electrostatic bonds between —COO- groups of the ligands and the positively charged (protonized) semiconductor surface. 

Bipyridine was first prepared one hundred years ago by the permanganate oxidation of 1,7-phenanthroline (42) to the dicarboxylic acid 43, followed by decarboxylation. Modifications of this method have been used. 2,3 -Bipyridine is among the products obtained from... 

Bipyridine (4) was first prepared in 1883 by the permanganate oxidation of 4,7-phenanthroline, followed by decarboxylation of the resultant dicarboxylic acid. Chromium trioxide may be used in the oxidation step. This method, sometimes with modifications, has been used on several occasions to prepare 3,3 -bipyridine and substituted 3,3 -bipyridines from the appropriate 4,7-phenanthroline " or 5,6-dihydro-4,7-phenanthroline. Closely related syntheses include the formation of... 

Methyl-3,3 -bipyridine has been oxidized by permanganate to 3,3 -bi-pyridine-4-carboxylic acid. " 3,3 -Bipyridine carboxylic acids are easily decarboxylated and have been esterified and converted to amides, hydrazides, and acylazides. The Hofmann degradation, of the diamide of 3,3 -bipyridine-2,2 -dicarboxylic acid affords the expected 2,2 -diamino-3,3 -bipyridine, but some of the tricyclic system 108 is formed as well. A 2,2 -bis(acylazide) is converted to a similar tricyclic system with ethanol via the intermediate isocyanate, and several related reactions have been described. The simultaneous dehydration... 

The lowest energy MLCT transition of Ru polypyridyl complexes of the type tris-[Ru(4,4/-dicarboxy-2,2/-bipyridine)3] (1), can be lowered so that it absorbs more in the red region of the visible spectrum by replacing one 4,4/-dicarboxy-2,2/-bipyridine (dcbpy) with two thiocyanate donor ligands [Ru(dcbpy)2(NCS)2] (2). In complex 2, the two 4,4/-dicarboxylic acid 2,2 -bipyridine ligands pull while the two thiocyanate donor ligands push electrons. The oxidation potential of the complex 2 is 0.85 V vs. SCE, which is cathodically shifted significantly (0.65 V vs. SCE) compared to the homoleptic type of complex 1, which shows Ru(III/II) couple at 1.5 V vs. SCE. Thus, the... 

Bedja, I. Hotchandani, S. Kamat, P. V. Preparation and characterization of thin Sn02 nanocrystalline semiconductor films and their sensitization with bis(2,2 -bipyridine)(2,2 -bipyridine-4-4 -dicarboxylic acid)ruthenium complex, J. Phys. Chem. 1994, 98, 4133. 

Dabestani, R. Bard, A. J. Campion, A. Fox, M. A. Mallouk, T. E. Webber, S. E. White, J. M. Sensitization of titanium dioxide and strontium titanate electrodes by ruthenium(II) tris(2,2 -bipyridine-4,4 -dicarboxylic acid) and zinc tetrakis(4-carboxy-phenyl)porphyrin An evaluation of sensitization efficiency for component photo-electrodes in a multipanel device, J. Phys. Chem. 1988, 92, 1872. 

SYNS BAY 1518 (2,4 -BIPYRIDINE)-3, 5 -DICARBOXYLIC ACID, l ,4 -DIHYDRO-2, 6 -DIMETHYL-,-DIETHYL ESTER ISOCINCHOMERONIC ACID, 1,4-DIHYDRO-2,6-DIMETHYL-4-(2-PYRIDYL)-, DIETHYL ESTER 3,5-PYRIDINEDICARBOXYLIC ACID, 1,4-DIHYDRO-2,6-DIMETHYL-4-(2-PYRIDYL)-, DIETHYL ESTER... 

The effect of the salt bridge on electron transfer can be determined directly by a comparative kinetics study of a D—[amidinium-carboxylate]—A complex and its switched interface D—[carboxylate-amidinium]—A congener. We have reported such a study for a supramolecular series of complexes where the donor is a ruthenium(II) polypyridyl with one bipyridine (bpy) ligand modified by either amidinium or carboxylate and the acceptor is the complementarity modified 3,5-dinitrobenzene (DNB) [162, 163]. The same donor-acceptor pair bridged by a symmetrical dicarboxylic acid interface has also been examined. 

Following the work of Whitesides, Hamilton reported a cyclic assembly based on a biphenyl-3,3 -dicarboxylic acid and an isophthalpyl bis(aminopyridine) (Fig. 10).25 The four-component assembly, of composition 2(acid) 2(bipyridine), was held together by eight hydrogen bonds. The components adopted a figure-of-eight structure in the solid state, wherein the diacids and bipyridines participated in face-to-face 7i-7i forces. 

As with the three polymeric examples, bipyridine ligands have been incorporated into polypeptides at the chain end, in the backbone, and as attached substituents. Specifically, a bipyridine has been coupled to either the amino or acid terminus of polypeptides to afford biological macroligands. For example, the 4,4 -dicarboxylic acid bipyridine was coupled to two 14-unit o-helices in order to analyze the conformation of the parallel structures.272 A triple-helical synthetic metallo-protein was formed through metal-templated self-assembly of a bipyridine unit with a 15-residue peptide substituted in the presence of metal ions.273... 

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