Addition compounds nitric acid

The bath components for a nitrite—nitrate accelerated bath basic to this conversion coating process are (/) 2inc metal or 2inc oxide dissolved in acid (2) phosphate ions added as phosphoric acid (J) addition of an oxidant such as sodium nitrite and (4) addition of nitric acid. Other oxidants such as peroxide, chlorate, chlorate in combination with nitrate, or an organic nitro compound may also be used. 

Formation of the partially saturated nitro derivatives 60 and 61 was reported by a Russian team <1994KGS1129>. The two products were obtained under fairly complicated reaction conditions when aminotetrazole 42 was first treated with potassium amidosulfonate and formaldehyde at pH = 4 followed by addition of nitric acid, methylamine, and acetic anhydride, product 60 was obtained in 24% yield. The same reaction, however, carried out at pH = 6 gave rise to formation of the acetoxy compound 61 in 21% yield. 

If ethylene is treated with nitrating acid, nitroethyl nitrate, N02.CH2.CH20N02 is produced, as has already been mentioned. The nitroethyl alcohol which is first formed by addition of nitric acid is fixed by esterification, whereas the addition compound with HNOs which is first formed at the double bond of benzene is decomposed with elimination of H20 for reasons which have been mentioned repeatedly. This case is therefore analogous to the reactions of bromine with ethylene and with benzene (p. 106). 

The addition of nitric acid increases the solubility of which of the following compounds ... 

The present procedure represents a modification of two previously published procedures,2 3 and results in a safer, more convenient preparation of the title compound. In Step A, the ratio of reagents has been adjusted to allow for the formation of only pentaerythrityl tetrachloride and trichlorohydrin none of the dichlorinated product is produced. Thus work up of the reaction is easier the product can be filtered rather than extracted, so minimal solvent is used, and the crude products are used in Step B, thus avoiding a tedious distillation. Step B has also been modified to make it safer and more convenient. The crude material from Step A is used, and addition of nitric acid over a longer period reduces the hazards of this step. Previously, it was noted that after the nitric acid was added in one portion and the mixture was heated, "a reaction became apparent, whereupon the flask was lowered rapidly into a waiting cold bath and the operator withdrew. 2 Step C is a more detailed modification of the procedure reported by the Russian workers3 as an improvement to the original method of Mooradian and Cloke.2 The latter used quinoline to catalyze the conversion of tris(chloromethyl)acetic acid to 3-chloro-2-(chloromethyl)propene. 

ADDITION OF NITRIC ACID, NITROGEN OXIDES AND RELATED COMPOUNDS TO UNSATURATED BONDS... 

Betaine Additive Compounds with Acids (Explosive) can be prepd by treating betaine with an acid rich in oxygen, such as nitric, chloric or perchloric. In the case of dichromate and permanganate additives, where the acids do not exist in the free state, the corresponding K or Na salts mixed with sulfuric acid can be used for treating the betaine Betaine Chlorate, CSH, 1N02.HCl03, wh monocl... 

Arsenical or mercury compounds are detected by evaporating a quarter of a litre of the ink and heating the extract with 1-2 c.c. of concentrated sulphuric acid and 5-10 c.c. of fuming nitric acid until nitrous vapours are eliminated, the addition of nitric acid and the heating being repeated until a perfectly colourless liquid is obtained (Rothe). The sulphuric add is then expelled and the residue tested for arsenic and mercury by the ordinary analytical methods. 

Measurements of the vapour pressures of solutions of nitric acid in ether carried out by Dalmon and his co-workers confirmed the existence of the compound. It was shown that the vapour pressure of ether, which at 0°C was 185 mm Hg, decreased on addition of nitric acid and attained 1 mm Hg when equimolar proportions of the two components were present in the solution. 

The ability of nitrogen dioxide to form addition products with aromatic compounds has been proved with polycycloketones. Thus, Lukin and Dashevskaya [56] found that benzanthrone formed an addition product with two N02 molecules. There is no doubt that the presence of carbonyl groups affects the ability to form addition products just as it does in the addition of nitric acid (pp. 54-55). 

If the compound is PbsCPOalsBr, the addition of nitric acid to a small sample will dissolve the compound but leave a precipitate of PbBrj (Table 8, solubility rule 3). If the compound is Pb5(P04)30H, the compound will dissolve and leave no residue. 

The nitro group most frequently substitutes a hydrogen atom, however other atoms or groups can also be substituted (e.g., halogen atoms). Nitro compounds can also be formed by addition of nitric acid or nitrogen oxides to unsaturated compounds (olefins, acetylenes). 

CCls CHO. A colourless oily liquid with a pungent odour b.p. 98°C. Manut actured by the action of chlorine on ethanol it is also made by the chlorination of ethanal. When allowed to stand, it changes slowly to a white solid. Addition compounds are formed with water see chloral hydrate), ammonia, sodium hydrogen sulphite, alcohols, and some amines and amides. Oxidized by nitric acid to tri-chloroethanoic acid. Decomposed by alkalis to chloroform and a methanoate a convenient method of obtaining pure CHCI3. It is used for the manufacture of DDT. It is also used as a hypnotic. 

Certain features of the addition of acetyl nitrate to olefins in acetic anhydride may be relevant to the mechanism of aromatic nitration by this reagent. The rapid reaction results in predominantly cw-addition to yield a mixture of the y -nitro-acetate and y5-nitro-nitrate. The reaction was facilitated by the addition of sulphuric acid, in which case the 3rield of / -nitro-nitrate was reduced, whereas the addition of sodium nitrate favoured the formation of this compound over that of the acetate. As already mentioned ( 5.3. i), a solution of nitric acid (c. i 6 mol 1 ) in acetic anhydride prepared at — 10 °C would yield 95-97 % of the nitric acid by precipitation with urea, whereas from a similar solution prepared at 20-25 °C and cooled rapidly to —10 °C only 30% of the acid could be recovered. The difference between these values was attributed to the formation of acetyl nitrate. A solution prepared at room... 

The authors of this work were concerned chiefly with additions to alkenes, and evidence about the mechanism of aromatic nitration arises by analogy. Certain aspects of their work have been repeated to investigate whether the nitration of aromatic compounds shows the same phenomena ( 5-3-6). It was shown that solutions of acetyl nitrate in acetic anhydride were more powerful nitrating media for anisole and biphenyl than the corresponding solutions of nitric acid in which acetyl nitrate had not been formed furthermore, it appeared that the formation of acetyl nitrate was faster when 95-98% nitric acid was used than when 70 % nitric acid was used. 

More information has appeared concerning the nature of the side reactions, such as acetoxylation, which occur when certain methylated aromatic hydrocarbons are treated with mixtures prepared from nitric acid and acetic anhydride. Blackstock, Fischer, Richards, Vaughan and Wright have provided excellent evidence in support of a suggested ( 5.3.5) addition-elimination route towards 3,4-dimethylphenyl acetate in the reaction of o-xylene. Two intermediates were isolated, both of which gave rise to 3,4-dimethylphenyl acetate in aqueous acidic media and when subjected to vapour phase chromatography. One was positively identified, by ultraviolet, infra-red, n.m.r., and mass spectrometric studies, as the compound (l). The other was less stable and less well identified, but could be (ll). 

The aHphatic iodine derivatives are usually prepared by reaction of an alcohol with hydroiodic acid or phosphoms trHodide by reaction of iodine, an alcohol, and red phosphoms addition of iodine monochloride, monobromide, or iodine to an olefin replacement reaction by heating the chlorine or bromine compound with an alkaH iodide ia a suitable solvent and the reaction of triphenyl phosphite with methyl iodide and an alcohol. The aromatic iodine derivatives are prepared by reacting iodine and the aromatic system with oxidising agents such as nitric acid, filming sulfuric acid, or mercuric oxide. 

Mercurous Nitrate. Mercurous nitrate [10415-75-5] Hg2N20 or Hg2(N02)2, is a white monoclinic crystalline compound that is not very soluble in water but hydrolyzes to form a basic, yellow hydrate. This material is, however, soluble in cold, dilute nitric acid, and a solution is used as starting material for other water-insoluble mercurous salts. Mercurous nitrate is difficult to obtain in the pure state directly because some mercuric nitrate formation is almost unavoidable. When mercury is dissolved in hot dilute nitric acid, technical mercurous nitrate crystallizes on cooling. The use of excess mercury is helpful in reducing mercuric content, but an additional separation step is necessary. More concentrated nitric acid solutions should be avoided because these oxidize the mercurous to mercuric salt. Reagent-grade material is obtained by recrystaUization from dilute nitric acid in the presence of excess mercury. 

In the examples, a nitro group is substituted for a hydrogen atom, and water is a by-product. Nitro groups may, however, be substituted for other atoms or groups of atoms. In Victor Meyer reactions which use silver nitrite, the nitro group replaces a hahde atom, eg, I or Br. In a modification of this method, sodium nitrite dissolved in dimethyl formamide or other suitable solvent is used instead of silver nitrite (1). Nitro compounds can also be produced by addition reactions, eg, the reaction of nitric acid or nitrogen dioxide with unsaturated compounds such as olefins or acetylenes. 

In addition to the conventional mixed acids commonly used to produce DNT, a mixture of NO2 and H2SO4 (8), a mixture of NO2 and oxygen (9), and just HNO (10) can also be used. TerephthaUc acid and certain substituted aromatics are more amenable to nitrations using HNO, as compared to those using mixed acids. For compounds that are easily nitratable, acetic acid and acetic anhydride are sometimes added to nitric acid (qv). Acetyl nitrate, which is a nitrating agent, is produced as an intermediate as follows ... 

Ammonia and nitric acid are the two basic ingredients in the manufacture of ammonium nitrate. In addition to consuming ammonia directly, the manufacture of ammonium nitrate consumes ammonia by way of nitric acid production. The largest single use of nitric acid is that of ammonium nitrate production (see Ammonium compounds). Urea (qv) is manufactured by reacting ammonia and carbon dioxide. Urea manufacturing faciHties are often located close to ammonia plants. 

Nitrating cellulose with pure HNO is the simplest method of obtaining CN. In practice, nitration does not occur with acid concentrations below 75%. At acid concentrations <75%, an unstable compound (so called Knecht compound) is formed which has been described as a molecular complex or an oxonium salt of the nitric acid (72). HNO concentrations of 75—85% yield CN with 5—8% N, which dissolve in excess acid. CN with % N of 8—10% are formed at acid concentrations of 85—89%. Above 89%, a heterogeneous nitration occurs without apparent swelling of the cellulose fibers. CN with 13.3% N can be obtained with 100% HNO. Addition of inorganic salts to 100% HNO can raise the % N to 13.9. 

The nitration route shows insufficient alpha-selectivity in addition to producing considerable dinitro product. Although a large amount of work has been done to maximize the yield of 1-nitro compound, the best result is less than 80%. Several methods have been developed to remove 2-nitroanthraquinone and dinitroanthraquinones from cmde 1-nitroanthraquinone. Purification is carried out, for example, by recrystaUization from nitric acid, or from organic solvents (15). 

Nitric acid acidulation NO, gaseous fluoride compounds Scrubber, addition of urea... 

The existence of the nitronium ion in sulfuric-nitric acid mixtures was demonstrated both by cryoscopic measurements and by spectroscopy. An increase in the strong acid concentration increases the rate of reaction by shifting the equilibrium of step 1 to the right. Addition of a nitrate salt has the opposite effect by suppressing the preequilibrium dissociation of nitric acid. It is possible to prepare crystalline salts of nitronium ions, such as nitronium tetrafluoroborate. Solutions of these salts in organic solvents rapidly nitrate aromatic compounds. ... 

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