Cobalt nitrobenzene

Trim ethyl-2,4,6-tri nitrobenzene Trinitroacetic acid Trinitroacetonitrile Trinitroamine cobalt... 

Treatment of 4-substituted phthalic acid derivative 3 with cobalt(II) sulfate, urea, ammonium chloride and ammonium molybdate(VI) in nitrobenzene at 180°C for six hours provided phthalocyanine 4 in 80% yield.421... 

The electrochemisty of ITIES is developing mainly on the basis of the studies of the water-nitrobenzene and water-1,2-dichloroethane interfaces. The polarizability ranges of these interfaces in the presence of typical electrolytes (Scheme 13) are about 0.30 V. Extension of these ranges has been achieved using other organic ions or/and solvents [2,8]. For example, TBA ions may be substituted by tetraphenylarsonium crystal violet cations and TPhB ions by dicarbollyl cobaltate (III) anions [1,2]. 

The organic solvent should feature a low solubility in water and a high dielectric constant. Numerous studies have been reported for liquid-liquid junctions involving DCE [43,62,70,71,73], nitrobenzene [67,68,74,75], and nitrophenyloctylether (NPOE) [56]. Various hydrophobic electrolytes have been employed in these solvents. Tetraphenylarsonium (TPAs+) [[71,75,76], bis-triphenylphosphoranylidene (BTPPA+) [43,50], and hydrophobic tetra-arylammonium [77,78] are among the cations used in the organic phase. The choice for anions has been mostly restricted to borate derivatives, tetraphenylborate (TPB ) [70,79,80], tetrakis(4-chlorophenyl)borate (TPBCH) [43,81,82], and tetrakis(penta-fluoro)phenylborate (TPFB ) [49,83], as well as dicarbollyl-cobaltate [75]. 

The highly oxophilic nature of the cobalt powder was readily demonstrated by its reaction with nitrobenzene at room temperature. Reductive coupling was quickly effected by 2 to give azo- and azoxy derivatives. Nitrobenzene reacted with 2 to give azobenzene in yields up to 37%. In some cases small amounts of azoxybenzene were also formed. With 1,4-diiodonitrobenzene, 2 reacted to give low yields of 4,4-diiodoazoxy-benzene and 4,4-diiodoazobenzene. 

Hassan et al [65] used a method for the determination of primaquine and other antimalarials, through ternary complex formation. The analytical aspects of the reaction between the widely used antimalarial drugs with cobalt and thiocyanate to form ternary complexes are described. Alternatively, determination of the cobalt content of the nitrobenzene extract using atomic absorption spectroscopy provided an indirect method for the determination of the drugs. Both methods are applied to the analysis of pharmaceutical preparation and the results obtained agreed well with those obtained with official methods. 

The carbon dioxide anion-radical was used for one-electron reductions of nitrobenzene diazo-nium cations, nitrobenzene itself, quinones, aliphatic nitro compounds, acetaldehyde, acetone and other carbonyl compounds, maleimide, riboflavin, and certain dyes (Morkovnik and Okhlobystin 1979). The double bonds in maleate and fumarate are reduced by CO2. The reduced products, on being protonated, give rise to succinate (Schutz and Meyerstein 2006). The carbon dioxide anion-radical reduces organic complexes of Co and Ru into appropriate complexes of the metals(II) (Morkovnik and Okhlobystin 1979). In particular, after the electron transfer from this anion radical to the pentammino-p-nitrobenzoato-cobalt(III) complex, the Co(III) complex with thep-nitrophenyl anion-radical fragment is initially formed. The intermediate complex transforms into the final Co(II) complex with the p-nitrobenzoate ligand. 

The reaction of o-nitrobenzaldehydes with some benzene derivatives in the presence of strong acid (H2S04, PPA) is a classical synthesis of acridinol N-oxides (373) (37BSF240) The synthesis works for benzyl alcohol, benzene, toluene and halobenzenes, but not for benzoic acid, benzonitrile, dimethylaniline, or nitrobenzene. Isoquinoline N-oxides (374) have been obtained from o-bromobenzaldoxime or the acetophenone derivative, and active methylene compounds with copper bromide and sodium hydride (77S760). The azobenzene cobalt tricarbonyl (375) reacts with hexafluorobut-2-yne to give a quinol-2-one (72CC1228), and the 3,4,5-tricyanopyridine (376) is formed when tetracyanoethylene reacts with an enaminonitrile (80S471). 

The liquid polymer is converted to the rubbery state by reagents that react with mercaptan (-SH) and side groups of the polymer segments by oxidation, addition or condensation to effect sulfide (-S-S-) bond formation. The oxidation reactions are exothermic and accelerated by an alkaline environment. The most commonly employed oxidizing agents which are suitable for curing liquid polymers are cobalt or manganese or lead octoate, p-quinonedioxime and di- or tri-nitrobenzene. Epoxy resin also reacts with liquid polysulfide polymers by addition in the presence of an aliphatic or aromatic amine and polyamide activator as shown in Equation 5.8 ... 

Reduction of Nitrobenzenes. Nitrobenzene was injected in small increments into 200 ml. of prehydrogenated (258 ml. of H2) cyanocobaltate(II) solution (0.15M cobalt, GN/Co = 5.1). After an induction period of approximately 4 minutes, hydrogen absorption commenced ... 

Since it was observed that absorption ceased after 3.3 atoms of hydrogen were taken up per mole of nitrobenzene, Equation 14 is shown as producing 4 moles of cyanocobaltate(II) per mole of substrate via reaction of the latter with CoH. Since further absorption of hydrogen occurred only upon introduction of alkali, it is implied that an intermediate complex, X, is formed which is not subject to further reaction with CoH but may be decomposed by alkali. The stoichiometry of this equation requires formulation of complex X as [Co(CN)5(C6H5NH)]—3. However, since absorption ceased after two atoms of hydrogen had been absorbed per atom of cobalt present, it is implied that a binuclear complex is formed, perhaps involving phenylhydroxylamine, azobenzene, or some other reduction intermediate. 

Substituted nitrobenzenes gave similar results on reduction of less than stoichiometric quantities in the absence of added alkali, hydrogen atom-substrate ratios of 3.0 to 4.1 being obtained while cessation of hydrogen absorption occurred at H/Co = 2.0 in all cases. Azoxy and azo compounds were isolated from o-nitrotoluene (H/substrate = 3.9) p-nitrotoluene (H/substrate = 3.2) yielded a mixture of azoxy and hydroxylamine derivatives, the latter believed to be the immediate precursor of the bimolecular product. Reduction of o-nitro-anisole in the presence of added alkali (NaOH, 3.3X cobalt concentration)... 

Chemicals which can damage (a) the liver include carbon tetrachloride, paracetamol, bromobenzene, isoniazid, vinyl chloride, ethionine, galactosamine, halothane, dimethyl-nitrosamine (b) the kidney include hexachlorobutadiene, cadmium and mercuric salts, chloroform, ethylene glycol, aminoglycosides, phenacetin (c) the lung include paraquat, ipomeanol, asbestos, monocrotaline, sulfur dioxide, ozone, naphthalene (d) the nervous system include MPTP, hexane, organophosphoms compounds, 6-hydroxydopamine, isoniazid (e) the testes include cadmium, cyclophosphamide, phthalates, ethanemethane sulfonate, 1,3-dinitrobenzene (f) the heart include allylamine, adriamycin, cobalt, hydralazine, carbon disulfide (g) the blood include nitrobenzene, aniline, phenyl-hydrazine, dapsone. 

Matel, L., Cech, R., Macasek, F., Hermanek, S., Plesek, J. 1977. Radiolysis of the bis(l,2-dicarbollyl)cobalt(III) ion in nitrobenzene-bromoform mixture. I. A final product of radiolysis. Radiochem. Radioanal. Lett. 29 317-324. 

Platinum catalysts have been shown to be highly selective for the hydrogenation of halonitrobenzenes to haloanilines. A number of effective platinum catalysts or catalyst systems have been described in the literature, mostly in patents.96 Dovell and Greenfield found that the sulfides of the platinum metals and cobalt were highly selective in the hydrogenation of halo-substituted nitrobenzenes.117-119 There was no detectable dechlorination with the sulfides of palladium, platinum, rhodium, ruthenium, and cobalt no detectable debromination occurred with platinum sulfide trace debromination occurred with rhodium sulfide and cobalt sulfide and appreciable debromination occurred with palladium sulfide. Typical hydrogenations with 5% platinum sulfide on carbon catalyst are given in eqs. 9.52 and 9.53 with 2,5-dichloronitrobenzene and p-bromobenzene, respectively.118... 

In the extraction systems with octanoic acid, Gindin et al. (38) revealed that the formation of dimeric cobalt(II) and nickel(II) oc-tanoates tended to decrease with increasing dielectric constant of the organic solvent decane > benzene > a-chloronaphthalene > chloroform > nitrobenzene > 3-methyl-l-butanol. Because 3-methyl-l-butanol is a solvating solvent, no dimerization of Co(II) and Ni(II) octanoates was observed in this solvent. 

Cobalt(II) salts are effective catalysts for the oxidation of 1,2-glycols with molecular oxygen in aprotic polar solvents such as pyridine, 4-cyanopyridine, benzonitrile, DMF, anisole, chlorobenzene and sulfolane. Water, primary alcohols, fatty acids and nitrobenzene are not suitable as solvents. Aldehydic products are further oxidized under the reaction conditions. Thus, the oxidative fission of rram-cyclo-hexane-l,2-diol gives a mixture of aldehydes and acids. However, the method is of value in the preparation of carboxylic acids from vicinal diols on an industrial scale for example, decane-1,2-diol is cleaved by oxygen, catalyzed by cobalt(II) laurate, to produce nonanoic acid in 70% yield. ... 

Oxidation of aniline. Aniline is oxidized to nitrobenzene (39% conversion) by f-butyl hydroperoxide catalyzed by vanadium oxyacetylacetonate. Molybdenum compounds are somewhat less active tungsten and cobalt compounds are inactive.2... 

Attempts to oxidize cobalt phthalocyanine to a cobalt(III) derivative in neutral or basic solvent were unsuccessful 213). However, it is reported 80) that cobalt phthalocyanine is oxidized to nitratocobalt(III) phthalocyanine by nitric acid in nitrobenzene at 10°-20°C. Unfortunately no data were presented which excluded the alternative formulation of the complex as a nitric acid adduct of cobalt(II) phthalocyanine, which seems more likely. 

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