Compounds of the formula I ##STR1## in which X denotes hydrogen, fluorine, chlorine or bromine, Y and Z denote hydrogen, lower alkyl or lower alkoxy, M denotes sodium, potassium or one equivalent of calcium and L denotes a dipolar aprotic solvent, are obtained from compounds of the formula II ##STR2## in which X, Y and Z have the abovementioned meanings, and a metal cyanamide of the formula III M.sub.2 N--CN in which M has the abovementioned meaning, in a dipolar aprotic solvent, which after the reaction is substantially removed, whereupon a lower molecular weight aliphatic alcohol is added to the residue and the product precipitated is isolated. Nitrophenylureas of the formula IV ##STR3## in which X, Y and Z have the abovementioned meanings, are obtained from the compounds of the formula I by acid hydrolysis.
公式I的化合物,其中X表示氢、
氟、
氯或
溴,Y和Z表示氢、低级烷基或低级烷氧基,M表示
钠、
钾或一当量的
钙,L表示一个双极非质子溶剂,可从公式II的化合物中获得,公式II中X、Y和Z具有上述含义,以及公式III的
金属
氰胺,其中M具有上述含义,在双极非质子溶剂中反应后,该溶剂被基本去除,然后向残留物中添加较低分子量的
脂肪醇,并分离沉淀的产物。通过酸
水解可以从公式I的化合物中获得公式IV的
硝基苯脲,其中X、Y和Z具有上述含义。