Pyridine, structure

Copper(II), di-/Lt-bromobis[bromo(pyridine)-structure, 2, 108 Copper 8-hydroxyquinolinate biocidal activity mechanism, 1, 401 fungicide, 1, 399 Copper nitrotetrazole as propellants, 5, 837 Copper phthalocyanine, 1, 333-334 colour and constitution, 1, 345 Coproporphyrin, 4, 382 Coproporphyrin, dehydro-, 4, 382... 

Wild, D., Toth, G., and Humpf, H.-U., New Monascus metabolites with pyridine structure in red fermented rice, J. Agric. Food Chem., 51, 5493, 2003. 

Table 1 Diffraction and Spectroscopic Methods for Elucidation of Pyridine Structures... 

In these discussions, we have focused attention on details of the physical measurements which confer understanding of structure in pyridine based compounds bond lengths, bond angles, electronic levels in both ground and excited states, and the involvement of solvation, complexation and other environmental features. In the latter, we have, out of necessity, restricted ourselves generally to complexes in which the role of the pyridine structure is of paramount interest, for the whole of the available space could have been filled with lists of complexes incorporating these structures, but where they were of subordinate interest to some other feature, typically the mode of coordination of metallic ions. 

N2,N4,NkTripicrylmelamine (TPM) [Structure (2.31)] has been reported to be a moderately thermally stable explosive with performance a little better than that of TNT [75]. Subsequently, heterocyclic nitrogen atoms of TPM were systematically replaced [76, 77] with the C-nitro function to give nitro-substituted tris(picrylamino) derivatives of pyrimidine [Structure (2.32)], pyridine [Structure (2.33)] and benzene [Structure (2.34)] given in Figure 2.2. 

Dewar pyridines 14-18 revert to the corresponding pyridines 11-13 when heated at 160°C.32 Simple bond-energy summation indicates that the 2-aza Dewar pyridine structure should be energetically favored over the 1-aza structure the predominance of 1-aza structures for per-fluoro(pentaalkylpyridines) (vide supra) is explained by the higher steric congestion of the pen-tasubstituted 2-aza structures.32... 

Certain pyridines react with Grignard reagents in the 1,4-manner when substituted by electron-withdrawing groups such as a carboxamide <2000J(P1)4245, 2005JOC2000>. The intermediate dihydropyridine can conveniently be oxidized to the pyridine structure. An example of this is seen in the reaction of 6-chloronicotinic acid derivative 125 with an excess of o-tolylmagnesium chloride, followed by oxidation with 2,3-dichloro-5,6-dicyano-l,4-benzoquinone... 

Ring closure under Vilsmeier conditions leads to the pyridine structure (Equation 90) <1995JHC505>. 

Cross-linked resins of 2- or 4-vinyl-pyridine structure have been prepared by copolymerizing 2- or 4-vinyl-pyridine with divinylbenzene32). 

On the other hand if a pyridine structure which is amenable to halogenation is required, then the pyridine is halogenated and connected ready made with the rest of the molecular structure no special cyclisation being required. 

V. Successful 1,3- and 1,4-Halogen-Dance Reactions, Synthesis of the Core Pyridine Structure... 

Biniak and co-workers reported that nitric acid treatment of carbon materials results in the formation of pyridine structures and pyridine-N-oxide species at the expense of pyrrolitic moieties [105]. An increase in the intensity of the bands at 1330 and 880 cm respectively, characteristic of pyridine, pyridine-N-oxide, or pyridone structures suggested that the ammonia treatment incorporated nitrogen into the carbon aromatic lattice with the formation of pyridinelike structures. The assigmnent of other nitrogen-containing bonds that can be found on the carbon surface is presented in Table 2.4. 

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