Nitryl chloride

HN03-nH20 + H2S04-nS03 - HN08 + (1 + n)H2S04 HNOa + CISOsH H2SO4 + NOsCl 

Critical surveys have shown that the older methods for the preparation of nitryl chloride are inefficient and yield impure products.1-7 Reasonably pure nitryl chloride was first prepared by Schumacher and Sprenger1-3 in 1929 by the reaction of nitrosyl chloride with ozone the preparation from chlorosulfonic acid and nitric acid was reported later.4 Recently, Schmeisser has obtained nitryl chloride from nitrogen(Y) oxide and phosphorus(V) chloride.5 The reaction of chlorosulfonic acid with nitric acid8-10 is probably the most convenient method for preparing large quantities of nitryl chloride of satisfactory purity. 

Chlorosulfonic Acid. Chlorosulfonic acid is best purified by distillation11,12 of the technical product at atmospheric pressure in a glass apparatus protected from the atmosphere by a drying tube containing anhydrous calcium chloride. The fraction distilling at 149 to 151° at 745 mm. is collected and stored in a glass-stoppered bottle. 

Anhydrous Nitric Acid. One hundred per cent nitric acid may be prepared by distillation of a mixture of concen- 

Nitryl Chloride. Caution The operations are performed in a well-ventilated hood which is darkened to prevent photochemical decomposition of the product. All connections in the apparatus are of ground glass. Openings in the system are fitted with drying tubes containing anhydrous calcium chloride. 

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Nitryl chloride Ammonia, sulfur trioxide, tin(IV) bromide and iodide... 

With sodium azide, salts of secondary nitroparaffins rearrange to N-substituted amides (29). With SO2, primary or secondary nitroparaffins give imidodisulfonic acid salts (30). Potassium nitroform reacts quantitatively with nitryl chloride in ether to form tetranitromethane (31). 

In the photolysis of difiuorodiazirine (218) a singlet carbene was also observed (65JA758). Reactions of the difiuorocarbene were especially studied with partners which are too reactive to be used in the presence of conventional carbene precursors, such as molecular chlorine and iodine, dinitrogen tetroxide, nitryl chloride, carboxylic acids and sulfonic acids. Thus chlorine, trifiuoroacetic acid and trifiuoromethanesulfonic acid reacted with difiuorodiazirine under the conditions of its photolysis to form compounds (237)-(239) (64JHC233). 

As stated above under TNMe, in Ger during WWII, the prepn of TeNMe by this process was scaled up for use as an intermediate and as a substitute for nitric acid in the V-2 rocket (Ref 26). A pilot plant was built at Newark, NJ for prodn using this procedure. It was destroyed by an expln in 1953 and not rebuilt (Refs 33 44). Other prepns of lesser importance are by the action of Ag nitrite on iodotrinitro-methane (Ref 3) by the action of 90% nitric acid and 25% oleum on malononitrile, yield 45% (Ref 40) by the action of mixed acid on a number of aromatic nitrocompounds, of which nitrobenzene, dinitrobenzene, and nitronaphtha-lene gave the best yields (Ref 13a) and by the action of nitryl chloride on salts of TNMe. 

According to Urbafiski (Ref 74, Chapt 2), this order seems to require some alteration. For example, nitryl chloride has been found to be a definitely weaker nitrating agent than nitric acid and should have been placed before it. The nitronium ion, N02+, occurs in many mixed acid compns... 

Draw the Lewis structures that contribute to the resonance hybrid of nitryl chloride, CINQ, (N is the central atom). 

Nitryl chloride (NO2CI) also adds to alkenes, to give p-halo nitro compounds, but this is a free-radical process. The NO2 goes to the less-substituted carbon. Nitryl chloride also adds to triple bonds to give the expected l-nitro-2-chloro alkenes. The compound FNO2 can be added to alkenes by treatment with HF in HNOa or by addition of the alkene to a solution of nitronium tetrafluoroborate (NOJBF4, see 11-2) in 70% polyhydrogen fluoride-pyridine solution (see also 15-37). 

A novel, mild system for the direct nitration of calixarenes has been developed using potassium nitrate and aluminum chloride at low temperature. The side products of decomposition formed under conventional conditions are not observed in this system, and the p-nitro-calixarenes are isolated in 75-89% yields.17 Such Friedel-Crafts-type nitration using nitryl chloride and aluminum chloride affords a convenient system for aromatic nitration.18 Nitryl chloride was previously prepared either by the oxidation of nitrosyl chloride or by the reaction of chlorosulfonic acid with nitric acid. However, these procedures are inconvenient and dangerous. Recently, a mixture of sodium nitrate and trimethysilyl chloride (TMSC1) has been developed as a convenient method for the in situ generation of nitryl chloride (Eq. 2.6). 

Nitropropane Nitrosyl fluoride Nitrosyl perchlorate Nitrourea Nitrous acid Nitryl chloride Oxalic acid See under Nitromethane chlorosulfonic acid, oleum Haloalkenes, metals, nonmetals Acetones, amines, diethyl ether, metal salts, organic materials Mercury(II) and silver salts Phosphine, phosphorus trichloride, silver nitrate, semicarbazone Ammonia, sulfur trioxide, tin(IV) bromide and iodide Furfuryl alcohol, silver, mercury, sodium chlorate, sodium chlorite, sodium hypochlorite... 

The nitration reagents (NO2 Y) for electrophilic aromatic nitration span a wide range and contain anions Y such as nitric acid (Y = OH-), acetyl nitrate (Y = OAc-), dinitrogen pentoxide (Y = NO3-), nitryl chloride (Y = Cl-), TV-nitropyridinium (Y = pyridine) and tetranitromethane [Y = C(N02)3-]. All reagents contain electron-deficient species which can serve as effective electron acceptors and form electron donor-acceptor (EDA) complexes with electron-rich donors including aromatic hydrocarbons107 (ArH, equation 86). Excitation of the EDA complexes by irradiation of the charge-transfer (CT) absorption band results in full electron transfer (equation 87) to form radical ion... 

Methyl isocyanide, 0759 Nickel(II) cyanide, 0997 Nitrogen oxide, 4724 Nitrogen trichloride, 4143 Nitrosyl chloride, 4023 Nitrogen triodide, 4633 Nitryl chloride, 4025 Nitryl hypolluorite, 4304 Oxygen dilluoride, 4317... 

Nitrogen trilluoride, 4336 Nitrogen triodide, 4633 Nitrogen triiodide-silver amide, 4634 Nitrogen triiodide-ammonia, 4635 Nitrosyl chloride, 4023 Nitrosyl fluoride, 4302 Nitryl chloride, 4025 Nitryl fluoride, 4303... 

Nitrosyl tetrafluorochlorate, 3985 Nitrous acid, 4435 Nitryl chloride, 4025 Nitryl fluoride, 4303 Nitryl hypochlorite, 4026 Nitryl hypofluorite, 4304 Nitryl perchlorate, 4029 Osmium hexafluoride, 4370 Osmium(VIII) oxide, 4858 Oxygen (Gas), 4831 Oxygen (Liquid), 4832 Oxygen difluoride, 4317 Ozone, 4846... 

Abbreviations BSO, D.L-buthionine-. i -sulfoxime L , lipid alkyl radicals LH, lipid LO, Upid alkoxyl radicals LOO, Upid peroxyl radicals L-NAME, yV -nitro-L-arginine-methyl ester MBl, methylene bridge index (mean number of h -aUytic methylene positions per fatty add) NO, nitric oxide NOS, nitric oxide synthase NO, nitrite N02, nitrogen dioxide NO2CI, nitryl chloride O2 , superoxide OH, hydroxyl radical OL, epoxyaUyhc radical OLOO, epoxyperoxyl radical 0=NOO , peroxynitrite SNAP, S-nitroso-iV-acetyl-D.L-penicillamine SOD, superoxide dismutase contd. onp. 98, Subcellular Biochemistry, Volume 36 Phospholipid Metabolism in Apoptosis. 

Irradiation of gaseous formaldehyde containing an excess of nitrogen dioxide over chlorine yielded ozone, carbon monoxide, nitrogen pentoxide, nitryl chloride, nitric and hydrochloric acids. Peroxynitric acid was the major photolysis product when chlorine concentration exceeded the nitrogen dioxide concentration (Hanst and Gay, 1977). Formaldehyde also reacts with NO3 in the atmosphere at a rate of 3.2 x 10 cmVmolecule-sec (Atkinson and Lloyd, 1984). 

Nitrous acid, see Dimethylamine Nitrous oxide, see Aldicarb. Atrazine. Chloropicrin Nitro-o-xylenes, see oXylene Nitro-ro-xylenes, see ro-Xylene Nitryl chloride, see Formaldehyde y-Nonachlor, see Heptachlor 2,2, 3,3, 4,4, 5,5, 6-Nonachlorobiphenyl, see Pentachlorobenzene... 

Alkenes react with nitryl chloride to give jS-nitroalkyl chlorides, jS-chloroalkyl nitrites and vic-dichloroalkane products. Nitryl chloride reacts with enol esters to give o -nitroketones. ... 

Nitryl chloride and tetranitromethane also At-nitrate amines. However, competing At-nitrosation is a particular problem and results from a redox reaction between the nitrating agent and the amine. 

Deville first synthesized dinitrogen pentoxide in 1849 by reacting silver nitrate with chlorine gas. This reaction probably involves the initial formation of nitryl chloride and, accordingly, dinitrogen pentoxide can also be formed from the reaction of nitryl chloride or nitryl fluoride with a metal nitrate. These reactions are more of theoretical interest than of any practical value. 

Nitryl chloride is used as a nitrating agent in organic synthesis. For example, benzene may be converted to nitrobenzene. The compound also is a chlorinating agent in many preparative reactions. 

Nitryl chloride is prepared most conveniently by reacting chlorosulfonic acid with anhydrous nitric acid at 0°C ... 

An older preparation method involves passing dry chlorine gas slowly over dry silver nitrate heated to about 100°C. The gaseous reaction products are allowed to cool to low temperature. After several hours, nitryl chloride condenses to a pale yellowish-brown liquid. Chlorine is removed by purging with CO2. 

Nitryl chloride hydrolyzes in water forming nitric acid and hydrochloric acid ... 

Nitryl chloride is a strong oxidizing agent. It reacts explosively with reducing agents. It readily attacks many metals. 

Nitryl chloride reacts with many organics forming their nitro derivatives. Such Friedel-Crafts nitration is catalyzed by a Lewis acid, such as AICI3. An example is nitration of benzene to nitrobenzene ... 

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