Nitryl bromide

While the hydrolysis of N205 is believed to represent its major loss process, there are other possibilities that have potentially interesting implications under certain conditions. For example, N2Os reacts with the components of sea salt particles such as NaCl, NaBr, and Nal to form nitryl chloride, nitryl bromide, and nitryl iodide, respectively (e.g., Finlayson-Pitts et al., 1989a, 1989b Behnke and Zetzsch, 1990 Zetzsch and Behnke, 1992 Junkermann and Ibusuki, 1992 George et al., 1994 Behnke et al., 1994, 1997 Leu et al., 1995 Fenter et al., 1996 Barnes et al., 1991 Schweitzer et al., 1998) ... 

Finlayson-Pitts, B. J., F. E. Livingston, and H. N. Berko, Synthesis and Identification by Infrared Spectroscopy of Gaseous Nitryl Bromide, J. Phys. Chem., 93, 4397-4400 (1989b). 

None of these things happened when we tried this reaction. What did happen —and it took some puzzling to figure it out—was that it reacted with a nitrate ion as the solvent to give two chromate ions plus nitryl ion, and the nitryl ion made nitryl bromide which decomposes to bromine and N02. Incidentally, we found that... 

The stability of the nitryl halides follows the stabihty of the nitrosyl halides, F > Cl > Br > I. Nitryl bromide BrN02 exists in equilibrium with NO2/N2O4 at room temperature and can be studied spectroscopically. INO2 has a hfetime of only a few seconds at room temperature. 

Nitrations with Nitryl Bromide. Nitryl brcmide conpared with the chloride and fluoride, is quite unstable. Nitration experiments were carried out with solutions obtained by the halogen exchange of nitryl chloride with KBr (not separated from unchanged nitryl chloride and decomposition products) carried out in sulfur dioxide solutions at -20°, and using TiBri as catalyst. Yields of nitrations are lower than those obtained with nitryl chloride, due to the formation of more ring-brominated products (29). This can be attributed partly to free bromine being present from the decomposition of nitryl bromide and to the easier homolysis of nitryl bromide itself. 

The kinetics of the oxidation of aqueous HBr by nitric acid in the presence of HNO2 have been reinvestigated. A mechanism was proposed which is based on fast equilibria forming an intermediate, which reacts further in a slow stage. Nitryl bromide was put forward as this intermediate as an alternative to NgOsBr. The equilibria are reversed at high water concentrations and this effect has been used to estimate the hydration numbers of salts. 

Nitryl bromide, N02Br, decomposes into nitrogen dioxide and bromine. 

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

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... 

Other additions to the double bond of compounds in this series have not been studied extensively, but reports now indicate that several such additions can be accomplished efficiently. Nitryl iodide is, however, not added92 to the double bond of compound 45, but bromination in methanol, in the presence of barium carbonate, gives crystalline methyl 4,6-0-benzylidene-2,3-dibromo-2,3-dideoxy-a-D-altropyranoside in 70% yield.93 On treatment with potassium tert-butoxide in refluxing xylene, this compound undergoes elimination of the elements of hydrogen bromide to give methyl 4,6-O-benzylidene-2-bromo-2,3-dideoxy-a-D-t/ireo-hex-3-enopyranoside (46, R = Br) in 90% yield. Likewise, compound 45 reacts with acetyl hypobromite to give methyl 3-0-acetyl-4,6-0-benzylidene-2-bromo-2-deoxy-a-D-glu-... 

Nitrogen.—An indirect method of determining the electrophilic reactivity of nitrosyl chloride towards various substrates in aqueous solution has been proposed. The action of nitrosyl chloride, bromide, and thiocyanate or nitrosating agents in micellar systems has been studied, and the results were interpreted in terms of the competition of anions present in solution for sites at the surface of a cationic micelle. The kinetics of the oxidation of nitrite to nitrate by chlorine and bromine are complex and have been interpreted in terms of mechanisms involving the nitryl halides as intermediates ... 

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