| 摘要 |
Compounds of the formula I <IMAGE> 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 <IMAGE> in which X, Y and Z have the abovementioned meanings, and a metal cyanamide of the formula III M2N-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 <IMAGE> in which X, Y and Z have the abovementioned meanings, are obtained from the compounds of the formula I by acid hydrolysis.
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