Process for preparing 2-halo-5-halomethylpyridines

• US 5,229,519 A
• Filed: 03/06/1992
• Issued: 07/20/1993
• Est. Priority Date: 03/06/1992
• Status: Expired due to Fees

• Current Assignee: Reilly Industries, Inc. (VSI Holdings LLC)
• Original Assignee: Reilly Industries, Inc. (VSI Holdings LLC)
• Inventors: Scriven, Eric F. V., Zhang, Tony Y.
• Primary Examiner(s): Cintins, Marianne M.
• Assistant Examiner(s): Peabody, John
• Application Number:
  US07/846,898
• Time in Patent Office: 501 Days
• Field of Search: 546/250
• US Class Current: 546/250
• CPC Class Codes: C07D 213/61 Halogen atoms or nitro radicals

Abstract

Disclosed are preferred processes for preparing a 2-halo-5-halomethylpyridine compound. The preferred processes involve cyclocondensing a 2-halo-2-halomethyl aldehyde or ketone of the formula (II) ##STR1## to form a 2-halo-2-halomethylpyridine compound of the formula (III) ##STR2## wherein X is Cl or Br, Y is a cyano group or an aminocarbonyl group, and R, R¹, R² and R³ are, independently, H or an organic radical which does not interfere with the cyclocondensation.

Claims

1. A process for preparing a 2-halo-5-substituted pyridine compound, comprising:

halogenating an α

,β

-unsaturated aldehyde or ketone of the formula (I);

##STR8## wherein Y is a cyano or aminocarbonyl group, and R, R¹, R² and R³ are independently, H or an alkyl, alkenyl, alkynyl or aryl group having up to about 20 carbon atoms, to form a compound of the formula (II) ##STR9## wherein Y, R, R¹, R² and R³ have the same values as given above and X is Cl or Br, and, cyclocondensing the aldehyde or ketone of formula (II) to form a 2-halo-5-substituted pyridine compound of the formula (III) ##STR10## wherein Y, X, R, R¹, R² and R³ have the same values as given above.

2. The process of claim 1 wherein Y is a cyano group.

3. The process of claim 1 wherein Y is an aminocarbonyl group.

4. The process of claim 1 wherein X is Cl and R, R¹, R² and R³ are, independently, --H or a lower alkyl group.

5. The process of claim 4 wherein Y is a cyano group, R, R¹, R², R³ are each H, and the formed 2-halo-5-halomethylpyridine is 2-chloro-5-chloromethylpyridine.

6. The process of claim 4 wherein Y is an aminocarbonyl group, R, R¹, R², R³ are each H, and the formed 2-halo-5-halomethylpyridine is 2-chloro-5-chloromethylpyridine.

7. The process of claim 5, including the step of isolating the 2-chloro-5-chloromethylpyridine.

8. The process of claim 6, including the step of isolating the 2-chloro-5-chloromethylpyridine.

9. The process of claim 1 wherein R, R¹, R² and R³ are, independently, --H, an alkyl group or an aryl group.