A novel synthetic method for 1-(2, 4-dichlorophenyl)-4-methyl- 5-(4-chlorophenyl)-1H-pyrazole-3-carboxylic acid

A novel method for the synthesis of 1-(2,4-dichlorophenyl)-4-methyl-5-(4-chlorophenyl) -1H-pyrazole-3-carboxylic acid was reported. The target compound was prepared starting from 4-chlorobenzaldehyde, which is inexpensive and easily available starting material, via adol condensation, cyclization and oxidation with the total yield of 50.6%. The structures of intermediates and final product were determined by ¹H NMR and MS. The novel method with the advantages of shorten process, easily conducted procedure and relatively high yield is suitable for scale-up production.