Chloride nitrosyl

Nitrosyl chloride has been prepared from hydrogen chloride and nitrosylsulfuric acid,1 from sodium chloride and nitrosylsulfuric acid,2 from nitrogen dioxide and moistened potassium chloride,3 by the combination of nitric oxide and 

Caution This preparation should be carried out in a hood. A gas-drying tower A (Fig. 3), which has a capacity of 900 

Six hundred milliliters of concentrated hydrochloric acid (7.2 mols) is placed in the drying tower. A concentrated solution of 103.5 g. of sodium nitrite (1.5 mols) in approximately 150 ml. of water is placed in the dropping funnel. The dropping funnel is fitted with a two-hole rubber stopper, which is connected to an air line and to a manometer K. The solution of sodium nitrite is kept under a pressure of 100 mm. to ensure its flow into the hydrochloric acid and to prevent bubbles of nitrosyl chloride from backing up into the dropping funnel. The receiver I is surrounded with a mixture of solid carbon dioxide and acetone. 

When the receiver has been thoroughly cooled, a small stream of the sodium nitrite solution is allowed to flow into the hydrochloric acid. The rate of flow of the sodium nitrite solution must be carefully regulated to maintain a slow evolution of nitrosyl chloride. Excessive pressure may develop if the sodium nitrite is added too rapidly. When nitrosyl chloride is seen issuing from the drying tube J, the drying tube is stoppered. A precipitate of sodium chloride causes cloudiness in the hydrochloric acid, but this settles out, leaving a clear, red solution of nitrosyl chloride and sodium chloride in the hydrochloric acid. 

When all the sodium nitrite solution has run into the hydrochloric acid, the stopcock is closed and the stopper is removed from the drying tube J. After the reaction has subsided, tube H is then withdrawn, and if any of the nitrosyl chloride has solidified, it is allowed to melt while 

Submitted by Geoege H. Coleman, Gerald A. Lillis, and Gilbert 

Nitrosyl chloride has been prepared by passing nitrogen dioxide through moist potassium chloride,1 by the reaction of nitric oxide with chlorine,2 from nitrosylsulfuric acid and sodium chloride,3 and from nitrosylsulfuric acid and dry hydrogen chloride.4 

The procedure described here is a modification of the last method. The reactants used can be prepared easily, and the principal impurity in the crude product is hydrogen chloride from which nitrosyl chloride can be separated readily. 

It is necessary to carry out the preparation under a hood. About 200 ml. of fuming nitric acidt (sp. gr. 1.60) contained in a 350-ml. tube (test-tube shape) is cooled with ice and salt, and sulfur dioxide is passed into it fairly rapidly. The reaction is exothermic, and the rate of addition should be such that the temperature of the solution does not rise above 5°C. In 6 or 8 hours, the crystals of nitrosylsulfuric acid fill the space of the original liquid, forming a compact mass with a layer of dark fuming liquid 2 to 3 cm. 

The product contains considerable hydrogen chloride. It is transferred to a cold round-bottom flask which is attached to a fractionating column as illustrated in Fig. 9. The column is surrounded with acetone f and dry ice at — 45°C. A receiver of the type previously used is attached to the side arm of the fractionating column. Care should be exercised to exclude moisture from the system. A water bath containing water at 20°C. is placed about the flask, and the nitrosyl chloride refluxed for about 30 minutes. Nearly all of the hydrogen chloride is driven off. The temperature of the bath surrounding the column is then raised to about — 5°C. by removing some of the cold acetone and add- .  

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A similar reaction occurs with chlorine, to give nitrosyl chloride... 

Acid Halogenides. For acid halogenides the name is formed from the corresponding acid radical if this has a special name (Sec. 3.1.2.10) for example, NOCl, nitrosyl chloride. In other cases these compounds are named as halogenide oxides with the ligands listed alphabetically for example, BiClO, bismuth chloride oxide VCI2O, vanadium(lV) dichloride oxide. 

Nitrosothiol Nitroso thioproline Nitrosoureas Nitrostat Nitrosyl chloride... 

A photochemical partial synthesis of aldosterone (19) made the hormone available on an industrial scale for the first time (114). Corticosterone acetate (51 acetate) is treated with nitrosyl chloride in pyridine at 20°C to yield the 11-nitrite (115). Irradiation of (115) leads to rearrangement with formation of the C g-oxime (116). Removal of the oxime residue with nitrous acid furnishes aldosterone (19) in excellent yield. 

The cooled, dried chlorine gas contains - 2% HCl and up to 10% O2, both of which are removed by Hquefaction. A full scale 600-t/day plant was built by Du Pont ia 1975. This iastaHatioa at Corpus Christi, Texas operates at 1.4 MPa (13.8 atm) and 120—180°C and uses tantalum-plated equipment and pipes. Oxidation of HCl Chloride by JSHtricHcid. The nitrosyl chloride [2696-92-6] route to chlorine is based on the strongly oxidi2iag properties of nitric acid... 

The practical problems He ia the separatioa of the chlorine from the hydrogea chloride and nitrous gases. The dilute nitric acid must be reconcentrated and corrosion problems are severe. Suggested improvements iaclude oxidation of concentrated solutions of chlorides, eg, LiCl, by nitrates, followed by separation of chlorine from nitrosyl chloride by distillation at 135°C, or oxidation by a mixture of nitric and sulfuric acids, separating the... 

The U.S. domestic commercial potassium nitrate of the 1990s contains 13.9% N, 44.1% I+O, 0—1.8% Cl, 0.1% acid insoluble, and 0.08% moisture. The material is manufactured by Vicksburg Chemical Co. using a process developed by Southwest Potash Division of AMAX Corp. This process uses highly concentrated nitric acid to catalyze the oxidation of by-product nitrosyl chloride and hydrogen chloride to the mote valuable chlorine (68). The much simplified overall reaction is... 

Nitrosyl chloride (178), nitrosyl chloride—hydrogen fluoride (NOF -3HF, NOF -6HF) (179), nitrous acid—hydrogen fluoride solutions (180,181), or nitrogen trioxide (prepared in situ from nitric oxide and oxygen) (27) can be used in place of sodium nitrite in the dia2oti2ation step. 

Nitrosyl chloride, a product of the basic reaction, has no commercial value and is converted to salable chlorine and to nitric acid for recycling. 

The reactants are fed separately iato a stUl, from which the product is continuously removed by distillation (qv) (31). Isopropyl nitrate is a valuable engiae-starter fuel and can be used ia explosives (see Explosives and propellants) (32). The nitrite ester, isopropyl nitrite, can be prepared from the reaction of isopropyl alcohol and either nitrosyl chloride or nitrous acid at ambient temperature (33). The ester is used as a jet engine propellant (30). 

Limonene (+15) is an important raw material for producing (-)-carvone [6485-40-1]. The process uses nitrosyl chloride and proceeds via nitrosochloride and oxime (78,79). The (-)-carvone (40) is found as the main component of spearmint oil and the (+)-carvone produced from (—)-limonene has the characteristic odor of diU. 

Toray. The photonitrosation of cyclohexane or PNC process results in the direct conversion of cyclohexane to cyclohexanone oxime hydrochloride by reaction with nitrosyl chloride in the presence of uv light (15) (see Photochemical technology). Beckmann rearrangement of the cyclohexanone oxime hydrochloride in oleum results in the evolution of HCl, which is recycled to form NOCl by reaction with nitrosylsulfuric acid. The latter is produced by conventional absorption of NO from ammonia oxidation in oleum. Neutralization of the rearrangement mass with ammonia yields 1.7 kg ammonium sulfate per kilogram of caprolactam. Purification is by vacuum distillation. The novel chemistry is as follows ... 

Substitutedisoxazole-3,5-dicarboxylic acids have been prepared from ethyl nitroacetate and an aldehyde (63BCJii50). A related reaction leads to diethyl 4-hydroxyisoxazole-3,5-dicarboxylate (334) and involves the reaction of acetonedicarboxylic acid ester (333) with nitrosyl chloride (78JHC1519). 

The action of benzoylmethylides (471) and (472) with nitrosyl chloride produced the 2-trans products (473) and (474) (72T3845). 

Equations 4-8 illustrate some mild methods that can be used to cleave amides. Equations 4 and 5 indicate the conditions that were used by Woodward and Eschenmoser, respectively, in their synthesis of vitamin B,2- Butyl nitrite," nitrosyl chloride, and nitrosoniurn tetrafluoroborate... 

Nitrosyl chloride [2696-92-6] M 65.5, h -5.5°. Fractionally distilled at atmospheric pressure in an allglass, low temperature still, taking the fraction boiling at -4° and storing it in sealed tubes. 

Whereas sulfonyl halides have been known for a long time and, especially the chlorides, have become of great synthetic value, sulfonyl cyanides were unknown until 1968. They were first prepared by van Leusen and co-workers from the reaction of sulfonylmethylenephos-phoranes with nitrosyl chloride. The same group also investigated part of their chemistry. Since then, two more, completely different, methods of synthesis were published from sulfinates with cyanogen chloride,and by the oxidation of thiocyanates. ... 

Caution Part B must be conducted in an efficient hood to avoid exposure to toxic nitrosyl chloride. 

Nitrosyl chloride (Matheson Gas Products) with a purity specified as > 97% was used. Occasionally, the needle valve of the nitrosyl chloride tank clogs. After closing the tank, the valve is disconnected and flushed with acetone until the acetone remains colorless. The needle valve is reconnected after being dried with compressed air. 

Nitrosyl chloride also can be prepared conveniently from hydrochloric acid and sodium nitrite, ... 

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