Potassium compounds nitrite

Erdmann,1 in 1866, prepared the first member of this series, namely, ammonium tetranitrito-diammino-cobaltate, [Co(NH3)2(N02)4] NH4. The salt is sometimes referred to as Erdmann s salt on that account. Later, Gibbs prepared other salts of the same type, and showed that in these salts the cobalt atom, united with ammonia and acidic radicles, forms a negative radicle.2 Werner then showed that these salts form the connecting link between the neutral un-ionised complex triacido-triammino-eobalt compounds and the double salt, such as potassium eobalti-nitrite. Thus, by replacement of ammonia molecules by acid radicles a transition takes place from trinitrito-triammino - cobalt to potassium tetranitrito - diammino - cobaltate, [Co(NH3)2(N02)4]K, then to potassium pentamtrito-ammino-eobalfate. [Co(NH3)(N02)5]K, and finally to hexanitrito-cobaltate, [Co(N02)e]Iv3. Tetra-acido-diammino-cobaltates are therefore the salts of the acid tetra-acido-diammino-cobaltic acid, [Co(NH3)2R4]H. 

The best known of these compounds is potassium cobalti-nitrite, [Co(N02)6]K3.1 This salt was originally regarded as a double salt of cobaltic nitrite with potassium nitrite, and represented by the formula Co(NQ2)3.3KNOa. Such a formula, however, does not represent the reactions of the substance, as the nitrite radicle is held firmly, and nitrous aeid is not liberated when the compound is treated with cold dilute acids, as it would be if it were a double salt as the formula indicates. Molecular conductivity measurements also indicate that it is a complex salt comparable with the metal-ammines. Many compounds of cobalt of this type are known. They may be regarded as the salts of the complex acid hexanitrito-cobaltic acid, [Co (N02)6]H3. 

Rubber chemicals - [RUBBERCHEMICALS] (Vol 21) -potassium hydroxide m mfg of [POTASSIUM COMPOUNDS] (Vol 19) -sodium nitrite for [SODIUM COMPOUNDS - SODIUM NITRITE] (Vol 22)... 

A potassium ruthenium nitrite compound, whose exact composition is unknown, was added to the nitrate melt. The original compound was an amber color. Observation of the melt indicated the formation of black solids, which settled to the bottom of the reaction vessel, leaving a green, molten supernate. Distilled water dissolved the solidified and cooled melt and appeared to dissolve nearly all the ruthenium present. 

The iodine atom in iodobenzene (unlike that in the corresponding aliphatic compounds) is very resistant to the action of alkalis, potassium cyanide, silver nitrite, etc. This firm attachment of the iodine atom to the benzene ring is typical of aromatic halides generally, although in suitably substituted nitio-compounds, such as chloro-2,4-dinitrobenzene, the halogen atom does possess an increased reactivity (p. 262). 

N-Nitrosodiethylamine. Add 36-5 g. (51-5 ml.) of diethylamine slowly to the calculated quantity of carefully standardised 5A-hydra chloric acid cooled in ice (1). Introduce the solution of the hydi ochloride into a solution of 39 g. of sodium nitrite (assumed to be of 90 per cent, purity) in 45 ml. of water contained in a 250 ml. distilling flask. Distil the mixture rapidly to dryness. Separate the yellow upper layer of the nitrosamine from the distillate saturate the aqueous layer with soUd potassium carbonate and remove the nitroso compound which separates and add it to the main product. Dry over anhydrous potassium carbonate and distil. Collect the diethylnitrosamine at 172-173-5°, The yield is 41 g. 

Dissolve 20 g, (19 -6 ml.) of anihne in a mixture of 55 ml. of concentrated hydrochloric acid (1) and 55 ml. of water contained in a 350 ml, conical flask. Place a thermometer in the solution and immerse the flask in a bath of crushed ice (2) cool until the temperature of the stirred solution falls below 5°, Dissolve 16 g. of sodium nitrite in 75 ml. of water and chUl the solution by immersion in the ice bath add the sodium nitrite solution (3) in small volumes (2-3 ml. at a time) to the cold anihne hydrochloride solution, and keep the latter weh stirred with the thermometer. Heat is evolved by the reaction. The temperature should not be allowed to rise above 10° (add a few grams of ice to the reaction mixture if necessary) otherwise appreciable decomposition of the diazonium compound and of nitrous acid wih occur. Add the last 5 per cent, of the sodium nitrite solution more slowly (say, about 1 ml. at a time) and, after stirring for 3-4 minutes, test a drop of the solution diluted with 3-4 drops of water with potassium iodide - starch paper (4) if no immediate blue colour... 

In addition to CuCfi, some other compounds such as Cu(OAc)2, Cu(N03)2-FeCl.i, dichromate, HNO3, potassium peroxodisulfate, and Mn02 are used as oxidants of Pd(0). Also heteropoly acid salts comtaining P, Mo, V, Si, and Ge are used with PdS04 as the redox system[2]. Organic oxidants such as benzo-quinone (BQ), hydrogen peroxide and some organic peroxides are used for oxidation. Alkyl nitrites are unique oxidants which are used in some industrial... 

Camphene forms a well-defined nitrite, and a nitroso-nitrite, when treated in the following manner A well-cooled solution of camphene in petroleum ether is mixed with a saturated solution of sodium nitrite, and dilute acetic acid is added. The mixture is well stirred, being kept cool all the time. Camphene nitrosonitrite, CuHi NjOj, separates and on recrystallisation forms crystals which decompose at about 149°. The petroleum ether solution, which has been filtered off from this compound, is shaken with a concentrated solution of pK)tassium hydroxide, which removes camphene nitrosite, CjQHigNjOj, in the form of its potassium salt. When this is decomposed with acids it yields the free nitrosite. This compound is a greenish oil, with a pleasant odour, easily decomposing when heated to 50°. 

Testing for excess of nitrous acid at the end of the reaction. For this purpose starch-potassium iodide papers are best used, and these indicate nitrite in acid solution by turning blue instantaneously. With some practice, the nitrite reaction can be clearly distinguished from the coloration caused by certain diazo compounds, such as those bearing nitro substituents. The latter react only after 0.5 to 2 seconds. Often the difference becomes more marked after dilution of the diazo solution with concentrated hydrochloric acid. A properly conducted diazotization should exhibit on completion a very weak nitrite reaction, corresponding to an excess of about 10 4 m. 

When it is heated above 196°C, the mixture of this compound with chromium trioxide combusts. When it is submitted to friction or impact, the same mixture detonates violently. The same happens if it is heated with sodium nitrite. Nitrite gives rise to a detonation with potassium hexacyanoferrate (II) too. The dangerous site of these complex anions is the cyano group. 

The reaction of alkyl halides with metal nitrites is one of the most important methods for the preparation of nitroalkanes. As a metal nitrite, silver nitrite (Victor-Meyer reaction), potassium nitrite, or sodium nitrite (Kornblum reaction) have been frequently used. The products are usually a mixture of nitroalkanes and alkyl nitrites, which are readily separated by distillation (Eq. 2.47). The synthesis of nitro compounds by this process is well documented in the reviews, and some typical cases are listed in Table 2.3.92a Primary and secondary alkyl iodides and bromides as well as sulfonate esters give the corresponding nitro compounds in 50-70% yields on treatment with NaN02 in DMF or DMSO. Some of them are described precisely in vol 4 of Organic Synthesis. For example, 1,4-dinitrobutane is prepared in 41 -46% yield by the reaction of 1,4-diiodobutane with silver nitrite in diethyl ether.92b 1-Nitrooctane is prepared by the reaction with silver nitrite in 75-80% yield. The reaction of silver nitrite with secondary halides gives yields of nitroalkanes of about 15%, whereas with tertiary halides the yields are 0-5%.92c Ethyl a-nitrobutyrate is prepared by the reaction of ethyl a-bromobutyrate in 68-75% yield with sodium nitrite in DMF.92d Sodium nitrite is considerably more soluble in DMSO than in DMF as a consequence, with DMSO, much more concentrated solutions can be employed and this makes shorter reaction times possible.926... 

Redox compounds that contain both reducing and oxidizing groups in their molecules are, for example, tin (II) perchlorate, peroxyformic acid, ammonium dichromate, and the double salt potassium cyanide with potassium nitrite [43]. 

Several papers discuss the effects of oxygen alone or with other compounds on cyanide toxicity. Oxygen alone results in minimal antagonism in mice injected with potassium cyanide and only slightly enhances the antagonistic effects of sodium nitrite (Sheehy and Way 1968). The antidotal effect of sodium thiosulfate alone or in combination with sodium nitrite, was enhanced by oxygen. 

These compounds were to be subjected to conventional triflation by triflic anhydride, followed by treatment with potassium nitrite in DMF. It was expected that in all cases good inversion yields would be obtained with neighboring ester groups, whereas the inversion would be inefficient with benzyl groups. 

As discussed above, the nitro groups of tetranitromethane and trinitromethyl compounds are susceptible to nucleophilic attack. Both potassium iodide and alkaline hydrogen peroxide affect the reductive denitration of trinitromethyl groups to em-nitronitronates 1,1,1-trinitroethane (33) is quantitatively reduced to potassium 1,1-dinitroethane (24) on treatment with alkaline hydrogen peroxide. Nucleophiles such as potassium fluoride in DMF can displace nitrite anion from tetranitromethane. Various nucleophiles, including azide, chloride, fluoride and ethoxide have been used to displace one of the nitro groups from fluorotrinitromethane. 

Subsequently, Kato and Goto have reported the synthesis of 2- and 4-pyridinecarbox-aldoximes from 2- and 4-picoline with potassium amide and amyl nitrite in liquid ammonia at — 33°C, although they failed to obtain either of these oximes when the reaction was carried ont with sodium amide in liquid ammonia at room temperature in a sealed tube. Finally, in 1964, aUcyl-substituted heteroaromatic compounds and allyl-substituted benzenes were oximated in liquid ammonia at —33 °C with sodamide and an alkyl nitrite . 

Several types of corrosion inhibitors have been investigated in the last 20 years [53-55] these include calcium and sodium nitrites, sodium benzoate, sodium/potassium chromate, sodium salts of silicates and phosphates, stannous chloride, hydrazine hydrate, sodium fluorophosphate, permanganate, aniline and related compounds, alkalis, azides, ferrocyanide, EDTA and many chelating compounds. However, in terms of field practice and research data, nitrite-based compounds occupy a dominant position. 

The pyrazolo[3,4-c]pyridine 157 was a key intermediate in the synthesis of 4-deazaformycin A 158 (Equation 57) <2003JOC6466>. Compound 157 was synthesized in good yield by cyclization of the intermediate nitroso compound derived from 159 on treatment with potassium acetate, acetic anhydride, and isoamyl nitrite. This methodology was also applied to the synthesis of deazaformycin B 160 <2002SL1479>. 

More complex salts are also known belonging to the series. For instance, if a solution of nitro-pentammino-cobaltic chloride be treated with an aqueous solution of sodium cobaltic nitrite, Na3Co(N02)6, a yellowish-brown crystalline precipitate of nitro-pentammino-cobaltic cobalti-nitrite, [Co(NH3)5(N02)]3[Co(N02)6]2, is formed. Also the corresponding ferrocyanicle may be prepared by treating nitro-pentammino-salts with potassium ferrocyanide. The compound obtained is a reddish-yellow substance of composition [Co(NH3)5(NO,)], [Fe(CN )6].6H20. 

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