Processes for the preparation of pesticidal compounds

Patent metadata

Field	Value
Publication number	US-9255082-B2
Application number	US-201514717296-A
Country	US
Kind code	B2
Filing date	May 20, 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 for the selective mono-acylation of 3-chloro-1H-pyrazol-4-amine hydrochloride (1a)

which comprises acylating amine (1a) with acetic anhydride in the presence of a base, to yield amide (1b)

2. The method of claim 1 , wherein the base is an inorganic base.

3. The process of claim 1 , wherein the base is sodium bicarbonate.

4. The process of claim 1 , wherein the acylating is carried out at a temperature of from about 0° C. to about 10° C.

5. The process of claim 4 , wherein the acylating is carried out at a temperature of about 5° C.

6. The process of claim 1 , wherein the base is an inorganic base and the acylating is carried out at a temperature of from about 0° C. to about 10° C.

7. The process of claim 6 , wherein the inorganic base is sodium bicarbonate and the temperature is about 5° C.

8. The process of claim 1 , further comprising halogenating and reducing 4-nitropyrazole

with concentrated hydrochloric acid at a temperature between about 10° C. and about 20° C. with between about 1 equivalent and about 4 equivalents of triethylsilane and about 1 weight percent to about 10 weight percent palladium on alumina to provide 3-chloro-1H-pyrazol-4-amine hydrochloride (1a)

9. The process of claim 8 , wherein the halogenating and reducing is conducted in a polar protic solvent.

10. The process of claim 9 , wherein the polar protic solvent is methanol or ethanol.

11. The process of claim 8 , wherein the triethylsilane is used in an amount of about 2.5 equivalents to about 3.5 equivalents.

Assignees

• Dow Agrosciences Llc

Inventors

• Yang Qiang
• Lorsbach Beth
• Whiteker Gregory
• Roth Gary
• Deamicis Carl
• Clark Thomas
• Gray Kaitlyn
• Canturk Belgin
• Kane Elisabeth J
• Zhang Yu
• Muhuhi Joseck M

Classifications

• Y10S424/10

  Insect repellent · CPC title

• C07D401/04 Primary

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

• A01N43/56 Primary

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

• C07C321/16

  of a saturated carbon skeleton containing rings · CPC title

• C07C321/14

  of an acyclic saturated carbon skeleton · CPC title