Patent ID: 6812348
Filing Date: 2004-11-02
Classification: C07C,C07D,Y02P

Abstract:
A process for the preparation of 2-chloro-5-chloromethyl-1,3-thiazole, which comprises reacting 1,3-dichloro-1-propene with an oxidizing agent selected from peroxy acids, an acid/H2O2 mixture, inorganic or organic peroxides or hydroperoxides in a solvent selected from nitriles or chlorinated hydrocarbons to convert it to the corresponding epoxide, which isa1) converted directly to 2-amino-5-chloromethyl-1,3-thiazole by thiourea in a suitable solvent selected from C1-C6-carboxylic acids, halogenated aliphatic or aromatic hydrocarbons, ethers, ketones, amides, sulfoxides or nitriles and is then converted to 2-chloro-5-chloromethyl-1,3-thiazole by Sandmeyer diazotization in the presence of inorganic or organic nitrites in HCl or in mixtures of HCl and an organic polar solvent, optionally in the presence of a copper halide catalyst or a2) is first converted to the compound of the formula (I) wherein R is C1-C6 alkyl, by thiourea in the presence of an alcohol ROH, wherein R is C1-C6 alkyl, optionally in combination with a solvent selected from the group of C1-C6-carboxylic acids, halogenated aliphatic or aromatic hydrocarbons, ethers, ketones, amides, sulfoxides or nitriles and is then converted to a compound of the formula (II) wherein R is C1-C6 alkyl, by Sandmeyer diazotization, whereupon 2-chloro-5-chloromethyl-1,3-thiazole is obtained after ether cleavage and chlorination.