Processes for the preparation of pesticidal compounds

• US 9,901,095 B2
• Filed: 04/12/2017
• Issued: 02/27/2018
• Est. Priority Date: 10/17/2013
• Status: Expired due to Fees

• Current Assignee: Dow Agrosciences LLC (Corteva, Inc.)
• Original Assignee: Dow Agrosciences LLC (Corteva, Inc.)
• Inventors: Yang, Qiang, Lorsbach, Beth, Whiteker, Greg, Roth, Gary, DeAmicis, Carl, Clark, Thomas, Gray, Kaitlyn, Zhang, Yu, Muhuhi, Joseck M.
• Primary Examiner(s): Morris, Patricia L
• Application Number:
  US15/485,782
• Publication Number:
  US 20170215420A1
• Time in Patent Office: 321 Days
• Field of Search: 5462754
• CPC Class Codes: A01N 43/56 1,2-Diazoles; Hydrogenated 1,2-diazoles
• CPC Class Codes: C07D 401/04 directly linked by a ring-member-to-ring-member bond

Abstract

The present application provides processes for making pesticidal compounds and compounds useful both as pesticides and in the making of pesticidal compounds.

Claims

1. A process comprising:

(a) halogenating and reducing 4-nitropyrazole to produce

2. A process according to claim 1, wherein R¹ is C₁-C₄ haloalkyl.

3. A process according to claim 1, wherein R¹ is CH₂CH₂CF₃.

4. A process according to claim 1, wherein R¹ is CH₂(2,2-difluorocyclopropyl).

5. A process according to claim 1 further comprising oxidizing (2b) with an oxidizing agent comprising hydrogen peroxide to yield

6. The process of claim 1, wherein the base in step (b) or step (e) is sodium bicarbonate.

7. The process of claim 1, wherein step (b) is carried out at a temperature of from about 0°

C. to about 10°

C.

8. The process of claim 1, wherein the halopyridine in step (c) is 3-bromopyridine or 3-iodopyridine.

9. The process of claim 1, wherein the copper salt in step (c) is copper(I) chloride (CuCl), copper(II) chloride (CuCl₂), or copper(I) iodide (CuI).

10. The process of claim 1, wherein the copper salt in step (c) is copper(I) iodide (CuI).

11. The process of claim 1, wherein the base in step (c) is potassium phosphate (K₃PO₄).

12. The process of claim 1, wherein the amine in step (c) is N,N′

-dimethylethane-1,2-diamine.

13. The process of claim 1, wherein step (c) is carried out at a temperature of from about 50°

C. to about 110°

C.

14. The process of claim 1, wherein step (c) is carried out in the presence of a polar solvent.

15. The process of claim 2, wherein the polar solvent in step (c) is acetonitrile (MeCN), dioxane, or N,N-dimethylformamide.

16. The process of claim 1, wherein the reducing agent in step (d) is a hydride source.

17. The process of claim 16, wherein the hydride source in step (d) is sodium borohydride (NaBH₄).

18. The process of claim 1, wherein the acid in step (d) is a Lewis acid.

19. The process of claim 18, wherein the Lewis acid in step (d) is borontrifluoride etherate (BF₃.Et₂O).

20. The process of claim 1, wherein the base in step (f) is potassium hydroxide (KOH).