Processes for the preparation of pesticidal compounds

Patent metadata

Field	Value
Publication number	US-9255083-B2
Application number	US-201514718627-A
Country	US
Kind code	B2
Filing date	May 21, 2015
Priority date	Oct 17, 2013
Publication date	Feb 9, 2016
Grant date	Feb 9, 2016

Abstract

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

First claim

What is claimed is:

1. A process comprising:
(a) reacting 3-hydrazinopyridine dihydrochloride with glyoxylic acid to yield (E)-2-(2-(pyridin-3-yl)hydrazono)acetic acid (6a)

(b) reacting (E)-2-(2-(pyridin-3-yl)hydrazono)acetic acid (6a) with acrylonitrile and a source of chlorine, in the presence of a base, to yield 3-chloro-1-(pyridin-3-yl)-4,5-dihydro-1H-pyrazole-5-carbonitrile (6b)

(c) dehydrocyanating of 3-chloro-1-(pyridin-3-yl)-4,5-dihydro-1H-pyrazole-5-carbonitrile (6b), in the presence of a base, to yield 3-(3-chloro-1H-pyrazol-1-yl)pyridine (5b)

(d) nitrating 3-(3-chloro-1H-pyrazol-1-yl)pyridine (5b) with nitric acid (HNO 3 ) to yield 3-(3-chloro-4-nitro-1H-pyrazol-1-yl)pyridine (5c)

(e) reducing 3-(3-chloro-4-nitro-1H-pyrazol-1-yl)pyridine (5c) to yield 3-chloro-1-(pyridin-3-yl)-1H-pyrazol-4-amine (5d)

(f) condensing 3-chloro-1-(pyridin-3-yl)-1H-pyrazol-4-amine (5d) with acetaldehyde and reducing to yield 3-chloro-N-ethyl-1-(pyridin-3-yl)-1H-pyrazol-4-amine (1d)

(g) reacting 3-chloro-N-ethyl-1-(pyridin-3-yl)-1H-pyrazol-amine (1d) with an activated carbonyl thioether of formula X 1 C(═O)C 1 -C 4 -alkyl-S—R 1
wherein
R 1 is selected from the group consisting of C 1 -C 4 -haloalkyl and C 1 -C 4 -alkyl-C 3 -C 6 -halocycloalkyl and
X 1 is selected from Cl, OC(═O)C 1 -C 4 alkyl, or an activated carboxylic acid, to yield pesticidal thioether (1e),

2. The process of claim 1 , wherein step (a) is carried out in the presence of an acid.

3. The process of claim 2 , wherein the acid is hydrochloric acid.

4. The process of claim 1 , wherein step (a) is carried out in the presence of a protic solvent.

5. The process of claim 1 , wherein the source of chlorine in step (b) is N-chlorosuccinimide.

6. The process of claim 1 , wherein the base in step (b) is an inorganic base selected from the group consisting of a metal carbonate, a metal hydroxide, a metal phosphate, or a metal hydride.

7. The process of claim 6 , wherein the inorganic base is potassium bicarbonate.

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

9. The process of claim 1 , wherein the base in step (c) is selected from the group consisting of 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU), 1,5-diazabicyclo[4.3.0]non-5-ene (DBN), and potassium hydroxide.

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

11. The process of claim 10 , wherein the polar solvent is N,N-dimethyl-formamide (DMF), ethanol (EtOH), or tetrahydrofuran (THF).

12. The process of claim 1 , wherein step (d) is carried out in the presence of sulfuric acid.

13. The process of claim 1 , wherein step (d) is carried out at a temperature of from about −10° C. to about 30° C.

14. The process of claim 1 , wherein step (e) is carried out using iron as the reducing agent.

15. The process of claim 14 , wherein step (e) is carried out in the presence of acetic acid or ammonium chloride.

16. The process of claim 1 , wherein step (e) is carried out using palladium on carbon in the presence of H 2 gas as the reducing agent.

17. The process of claim 1 , wherein step (f) is carried out in the presence of sodium borohydride.

18. The process of claim 17 , wherein step (f) is carried out in a polar protic solvent.

19. The process of claim 1 , wherein R 1 is —CH 2 CH 2 CF 3 or —CH 2 (2,2-difluorocyclopropyl).

20. The process of claim 1 , wherein step (g) is carried out in the presence of sodium bicarbonate.

Assignees

• Dow Agrosciences Llc

Inventors

• Yang Qiang
• Lorsbach Beth
• Roth Gary
• Niyaz Noormohamed M
• Nissen Jeffrey
• Ross Jr Ronald
• Whiteker Greg
• Deamicis Carl
• Gray Kaitlyn
• Zhang Yu

Classifications

• C07D213/77 Primary

  Hydrazine radicals · CPC title

• A01N47/40

  the carbon atom having a double or triple bond to nitrogen, e.g. cyanates, cyanamides · CPC title

• A01N43/40

  six-membered rings · CPC title

• A01N43/56

  1,2-Diazoles; Hydrogenated 1,2-diazoles · CPC title

• C07D401/04 Primary

  directly linked by a ring-member-to-ring-member bond · CPC title