Methylamine nitrous acid action

Fulminic acid can be regarded as the simplest oxime. A number of compounds with an oxime group C=NOH can form salts which possess initiating properties, for example salts of nitroformoxime (methylnitrolic acid) (I) which can be obtained in a known way by the action of nitrous acid on nitromethane. Salts of form-hydroxamic acid (II), particularly the mercuric salt, also possess initiating properties [66]. Formhydroxamic acid can be obtained by the action of hydroxylamine on formic acid esters or by oxidation of methylamine. 

The original method of preparing diazomethane is as follows. Methyl-urethane, formed by the interaction of methylamine and chloroformic ester, is converted into the nitroso compound by the action of nitrous acid, the latter yielding diazomethane on treatment with alcoholic potash. 

An ethereal solution of diazomethane is usually prepared immediately before it is required for reaction. A convenient precursor for the generation of diazomethane is IV-methyl-lV-nitrosotoluene-p-sulphonamide which is prepared by the action of nitrous acid on N-methyltoluene-p-sulphonamide. This latter is formed from toluene-p-sulphonyl chloride and methylamine in alkaline solution. The methylnitrosamide affords diazomethane on reaction with potassium hydroxide solution. 

G) Action of Nitrous Acid on Amines. (1) Primary Amines. To 3 ml of methylamine solution in a test tube, add 3 ml of water and 2 g of solid sodium nitrite. Add slowly in small portions 2 ml of dilute sulfuric acid. After a few minutes, warm, and note the effect. What product remains behind By what test may its presence be detected ... 

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