Method for producing 2-chloro-5-chloromethyl-1,3-thiazole

A process for the preparation of 2-chloro-5-chloromethyl-1,3-thiazole, which is characterized in that

• (a) allyl isothiocyanate of the formula CH2═CH—CH2—NCS is reacted at a temperature of from −40° C. to 30° C., in a solvent that is inert under the reaction conditions, optionally in an inert gas atmosphere, with from 1 to 2 mol of a chlorinating agent per mol of allyl isothiocyanate, said chlorinating agent being selected from the group, consisting of Cl2, SO2Cl2, PCl3, PCl5 and POCl3;
• (b) to the reaction mixture resulting from step (a), at a temperature of from 0° C. to the boiling temperature of the reaction mixture, from 1 to 5 mol of an oxidizing agent per mol of allyl isothiocyanate are added, said oxidizing agent being selected from the group, consisting of Br2, an N-haloimide and a dihalodialkylhydantoin, optionally with the application of UV light and/or in the presence of a suitable initiator, optionally in an inert gas atmosphere;
• and
• (c) the 2-chloro-5-chloromethyl-1,3-thiazole is isolated from the reaction mixture resulting from step (b);
• and, if desired,
• (d) the isolated 2-chloro-5-chloromethyl-1,3-thiazole resulting from step (c) is converted by crystallization into high-purity 2-chloro-5-chloromethyl-1,3-thiazole.