Nitrosation of 3-alkyl-1-arylureas was investigated with sodium nitrite in 99% formic acid or with isoamyl nitrite in chloroform. The preparation of 3-alkyl-1-aryl-1-nitrosoureas was effectively performed by using isoamyl nitrite in the absence of acids, since the 1- nitrosoureas were isomerized to the 3-nitroso isomers by acids. The carbon-13 nuclear magnetic resonance and infrared spectral properties of the products were examined and ...
