| 摘要 |
A process for the preparation of an aryl cyanamide comprising reacting an arylamine of the formula <IMAGE> in which Ar is aryl, R is hydrogen or alkyl, and n is 1, 2 or 3, (excepting 2-nitroaniline, 4-nitroaniline and arylamines having a nucleophilic character equal to or lower than 2-nitroaniline and 4-nitroaniline), with cyanogen chloride in 1-2 times the molar amount per mole of amino group of the arylamine initially in a homogeneous liquid phase using as reaction medium acetic acid (which is optionally diluted with water and/or a water-miscible, organic auxiliary solvent) in the presence of 1-1.5 molar equivalents of an auxiliary base for each amino group of the arylamine, there being more cyanogen chloride than equivalents of auxiliary base present in the reaction mixture at any point in time of the reaction, the pH of the reaction mixture being maintained below 7.
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