1,2-Nitronitroso compounds

Sodium/alcohol 1,2-Alkoxynitro compounds from 1,2-nitronitroso compounds or 1,1-nitroethylene derivatives with formation of alkoxy from acoxy compounds... 

Lawson " found that aconitine was converted by nitrous acid into a substance, C3jH40Oj2Nj, crystallising in small, colourless prisms, m.p. 276° (dec.). Jacobs and Craig confirmed this observation but prefer the formula C34H44O13N2. Nitric acid converts this nitroso-derivative into the nitronitroso-compound, 0311135013X3, described above. 

In atmospheric chemistry, reactions between pure nitric oxide and a range of activated alkenes have been examined. However, no addition products were observed." Only in the presence of NO2 was addition to give jS-nitroalkyl radicals, followed by trapping to /3-nitronitroso compounds, observed. These final products can also trap other radicals to give aminoxyl radicals. 

Kuhn and von Klaveren190 recommend a mixture of nitric acid and 100% hydrogen peroxide for oxidation of 0-nitronitroso compounds. 

Another example is the nitrosation of creatinine in meat, by which 5-oxocreatinine-5-oxime and l-methyl-5-oxohydantoin-5-oxime can arise (Figure 12.32). Some phenols also react with nitrosation reagents yielding nitroso compounds and oximes. In addition to nitroso compounds and oximes, in reactions with nitrosation agents there also arise nitro, oxynitro and nitronitroso compounds, as in the case of polycyclic aromatic hydrocarbons (PAHs). The mechanisms of their formation and other aspects of their presence in food are not yet sufficiently known. An example is the nitrosation of p-coumaric acid, which is dependent on pH. Acidic pH results in 4-hydroxybenzaldehyde (16%), l d-dihydroxybenzeneacetaldehyde oxime (59%), 4-hydroxy-l -oxobenzeneacetaldehyde oxime (26%) and 7-hydroxy-l,2(4H)-benzoxazin-4-one (6%), whereas 4-(2-oxido-l,2,5-oxadiazol-3-yl)phenol was formed at acidic (6%) and neutral and alkaline pH (both 1%) (Figure 12.38). 

Acylation or sulfonation of hexamine leads to the diacyl bicyclic tetramines (331) which undergo ring opening in N204 to give the dinitrosotetrazocanes (332) in 50-80% yields. The latter can be further oxidized to nitronitroso or dinitro compounds (73JHC279). 

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