Process for preparing chloro-bis(alkylamino)-s-triazines

In a process for preparing chloro-bis(alkylamino)-s-triazine by step-wise replacement of two chlorine atoms of cyanuric chloride by means of alkylamino groups in an alkaline medium comprising water and a liquid organic compound which is a solvent for cyanuric chloride, in which a molar excess of alkylamine is used in the second replacement step, the method of suppressing the formation of tris(alkylamino)-s-triazines which comprises adding to the reaction mixture, after the second chlorine atom has been replaced with an alkylamino group, an oxidizing agent selected from the group consisting of hydrogen peroxide and alkali metal hypochlorites, persulphates and permanganates, in an amount of at least 1 equivalent for every mole of unreacted alkylamine present in the said reaction mixture.