Chlorination of 2-chloro-5-trichloromethylpyridine

• US 4,309,548 A
• Filed: 01/19/1981
• Issued: 01/05/1982
• Est. Priority Date: 01/19/1981
• Status: Expired due to Fees

• Current Assignee: The Dow Chemical Company (Dow, Inc.)
• Original Assignee: The Dow Chemical Company (Dow, Inc.)
• Inventors: Werner, John A., Wilson, Charles A.
• Primary Examiner(s): Rotman, Alan L.
• Application Number:
  US06/225,824
• Time in Patent Office: 351 Days
• Field of Search: 546/345, 546/346
• US Class Current: 546/345
• CPC Class Codes: C07D 213/61 Halogen atoms or nitro radicals

Abstract

2,3-Dichloro-5-trichloromethylpyridine is produced by selective liquid phase chlorination of 2-chloro-5-trichloromethylpyridine.

Claims

1. A process for preparing 2,3-dichloro-5-trichloromethylpyridine which comprises treating a reaction mixture containing 2-chloro-5-trichloromethylpyridine and a solvent or solvent mixture principally composed of N-methylpyrollidone, N,N-dimethylformamide, or dimethylsulfoxide with an excess amount of chlorine at a temperature of from about 55°

C. to about 120°

C. for a time sufficient to chlorinate at least some of the 2-chloro-5-trichloromethylpyridine to form 2,3-dichloro-5-trichloromethylpyridine.

2. The process of claim 1 wherein the solvent is principally N,N-dimethylformamide.

3. The process of claim 2 wherein the reaction mixture contains from about 5 mole percent to about 15 mole percent water.

4. The process of claim 2 wherein the temperature is from about 90°

C. to about 120°

C.