Hydroxylamine disulfonate

Allied-Signal Process. Cyclohexanone [108-94-1] is produced in 98% yield at 95% conversion by liquid-phase catal57tic hydrogenation of phenol. Hydroxylamine sulfate is produced in aqueous solution by the conventional Raschig process, wherein NO from the catalytic air oxidation of ammonia is absorbed in ammonium carbonate solution as ammonium nitrite (eq. 1). The latter is reduced with sulfur dioxide to hydroxylamine disulfonate (eq. 2), which is hydrolyzed to acidic hydroxylamine sulfate solution (eq. 3). 

Note 7) followed by a mixture of 550 cc. of concentrated hydrochloric add (sp. gr. 1.19) with 400 g. of shaved ice (Note 8). The entire solution should always remain below o°, further ice being added if there is a tendency for the temperature to rise. The solution should now become acid to Congo Red paper and contain 6 or more moles of the sodium hydroxylamine disulfonate, which rapidly hydrolyzes to an acid solution of the monosulfonate. 

The precipitated potassium hydroxylamine disulfonate is expeditely filtered from the cold liquid, and the moist salt is dissolved in 500ml of N/2 hydrochloric acid. The solution is heated on the water bath for two hours and then well cooled in ice while 59g of potassium bicarbonate is added in small portions (foaming ) to the liquid in order to neutralize the free acid formed in the hydrolysis. The final solution should be adjusted to a faint add reaction with... 

Reaction of Ferrous Nitrosyl Chelates with SOj /HSO. The reaction is known to produce a large number of products (12), including N2O, N2, hydroxylamine disulfonates (HADS), SO , 205 , and Fe. Reports of the reaction have indicated that it is complicated. There are contradictions in the literature as to what the reaction products are, as well as the kinetic behavior. 

Ethoxyamine Hydroxylamine disulfonic acid + ethyl sulfate... 

In the Raschig process, ammonium nitrite is converted to ammonium hydroxylamine disulfonate with sulfur dioxide in sulfuric acid at 273 K ... 

The reaction is reversible, but the state of equilibrium highly favors the desired products. Preparations of large quantities for synthetic work are illustrated for methyl ethyl ketoxime, cyclohexanone oxime, hept-aldoxime, and benzophenone oxime, the procedures varying somewhat with the nature of the carbonyl compound. In some instances, a readily available and cheap reagent like sodium hydroxylamine disulfonate, HON(SO,Na)j, is first prepared from sodium nitrite and sodium bisulfite and, without isolation, treated with the carbonyl compound, Hydioxylamine-O sulfonic add, Ii,NOSO,H, is still another reagent and, like sodium hydroxylamine disulfonate, is used in the absence of a base. The preparation of hydroxylamine hydrochloride is described. ... 

The resulting ammonium nitrite solution is reacted with sulfur dioxide at 0 to 5°C and pH 2 to 4.5 forming ammonium hydroxylamine disulfonate ... 

The reagent is prepared by oxidizing sodium hydroxylamine disulfonate with permanganate, removing the MnOi by filtration, and salting out with potassium chloride. Teuber and co-workers have studied extensively the oxidation of sub-... 

Derivation From hydroxylamine disulfonic acid and methyl sulfate. 

Preparation. Singhla reports an improved procedure for the preparation based on a patent by H.-J. Teuber. Hydroxylamine disulfonate, HON(SOaNa)2, is prepared from sodium nitrite, sodium bicarbonate, and sulfur dioxide and then oxidized with potassium permanganate with pH-control. Manganese dioxide is removed by centrifugation followed by filtration. Fremy s salt separates from the filtrate after addition of KC1 and is recrystallized from 1 N KOH. Material prepared in this way can be stored in the cold for several months. 

Further sulfonation to produce hydroxylamine disulfonate and amine trisulfonate. These sulfonates can hydrolyze to form sulfuric acid and reduced nitrogen species. The latter can undergo further reaction with bisulfite and nitrite. 

Formation of Hydroxylamine Disulfonate by Reaction of Nitrous Acid with Bisulfite Ion. Hydroxylamine disulfonate (HADS) is formed according to the following net reaction ... 

Hydrolysis of Hydroxylamine Disulfonate (HAPS). HADS hydrolyzes to give hydroxylamine monosulfonate (HAMS) and sulfates ... 

Sulfonation of Hydroxylamine Disulfonate. Seel et al. (14) studied the reaction between HADS and bisulfite and found that this reaction produced about 70% aminetrisulfonate (ATS) and 30% aminedisulfonate (ADS) in the temperature range from 25 to 60°C and ionic strength from 1.0 to 1.2 M, with reaction times ranging up to 4.5 hr at a pH of 7. The reaction proceeds according to Eqs. (14) and (15) ... 

Oblath, S. B., S. S. Markowitz, T. Novakov, and S. G. Chang (1981). Kinetics of the formation of hydroxylamine disulfonate by reaction of nitrite with sulfites. J. Phys. Chem. 85, 1017-1021. 

Other variations of the caprolactam process produce hydroxylamine disulfonic acid which is hydrolyzed to hydroxylamine sulfate and an ammonium sulfate by-product. Additional ammonium sulfate is produced downstream in the oximation step by the reaction of ammonia with sulfuric acid. Ammonium sulfate is a low value by-product and there is an advantage to producing hydroxylamine sulfate directly in order to avoid the production of unwanted ammonium sulfate downstream. The oxygen-based NO reduction process provides this advantage and the processes that use it are characterized as low by-product production processes. 

Hydroxylamine salts are made commercially in two ways the hydrolysis of primary nitroparaffins and the cathodic reduction of nitric acid. In the laboratory it is easiest to reduce nitrous acid with a bisulfite and then hydrolyze the resulting salt of hydroxylamine disulfonic acid. The reactions are as follows ... 

Dissolve 0.5 mole (42.5 grams) of potassium nitrite and 0.6 mole (58 grams) of potassium acetate in 200 ml of water in a 2-liter flask, and cool in an ice-salt freezing mixture to about — 5°. Add 750 grams of finely crushed ice, shaking frequently. (A mechanical stirrer is not satisfactory.) Pass sulfur dioxide slowly. A mass of crystals of potassium hydroxylamine disulfonate, H0 N(S03K)2 2H20, crystallizes out. When the odor of sulfur dioxide shows that an excess has been passed, filter off these crystals under suction and wash them with 100 ml of ice water. The yield is about 85 per cent. 

The hydroxylamine used for the reaction with cyclohexanone is obtained by the Raschig process or by catalytic hydrogenation of either nitric oxide or nitric add. In the Raschig process, the hydroxylamine is obtained in the form of its sulfate. The raw materials for this process are sulfur dioxide, ammonia, carbon dioxide, and water. A mixture of NO and NO2, as obtained from the catalytic oxidation of ammonia, is absorbed in an aqueous ammonium carbonate solution to yield ammonium nitrite, which is then reacted with SO2 in the presence of ammonium hydroxide. The product of this reaction is hydroxylamine disulfonate, which converts upon hydrolysis via the monosulfonic acid hydroxylamine into hydroxylamine sulfate ... 

The yellow species formed in the reaction between sodium nitrite and thiosulfate in acidic, aqueous solution has been identified as the 5-nitrosated thiosulfate (03SSN0) , which is suggested to be formed by parallel pathways involving the nitrosonium ion and dinitrogen trioxide. The much studied reaction between nitrite and sulfite to give hydroxylamine disulfonate has received further attention and some apparent discrepancies have been clarified. For the pH range 4.5 to 7 the rate equation is given by (11). 

Ammonium Nitrate 12 32-212 0-100 B E - - plus ammonium hydroxylamine disulfonate SO7. ammonium sulfates and nitrates. Alloy C = 0,3 mpy... 

Preparation of Sodium Hydroxylamine Disulfonate 39-2. Preparation of Methyl Ethyl Ketoxime 39-3. Preparation of Phenylglyoxime... 

A classical method of preparing a standard solution of sodium hydroxylamine disulfonate is given here. Some disagreement exists in the literature as to the exact nature of this reagent. Sometimes it is referred to as sodium hydroxylamine monosulfonate [3,4]. 

In a 5-liter flask equipped with an efficient stirrer and surrounded with a large ice-salt bath is placed 4-liters of distilled water, 325 gm (3 moles) of anhydrous sodium carbonate, and 420 gm (5.8 moles) of 95 % pure sodium nitrite. The mixture is stirred and cooled. When the temperature has reached — 5°C, sulfur dioxide is passed into the solution at such a rate that the solution temperature never exceeds 0°C. With efficient cooling, the reduction is completed in approximately 4 hr. The end of the reduction is indicated by a drop in the pH of the solution to the acid side. Just before the reaction turns acid, the solution becomes slightly brown in color. The solution is approximately 1.2 Af in sodium hydroxylamine disulfonate and may be used directly for the preparation of oximes. 

In using sodium hydroxylamine disulfonate, the reagent is treated with a carbonyl compound, warmed, and cooled. Only at this point is the reaction mixture neutralized with an alkaline solution [6]. This method is suitable for the preparation of a range of carbonyl compounds. Negative results were obtained in the case of benzil and qui-none monoxime, either because the oximes are not sufficiently soluble in the reaction medium or because the oximes produced are not stable in the acidic reaction solution. 

With suitable precautions, to 1 liter of the sodium hydroxylamine disulfonate solution from Preparation 39 2 (approx. 1.2 moles) is added 72 gm (1 mole) of methyl ethyl ketone. The mixture is warmed to TO C. Then the reaction flask is wrapped with insulation and allowed to cool slowly for 12 hr. 

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