Process for the preparation of 4-alkoxy-3-acetoxypicolinic acids

Patent metadata

Field	Value
Publication number	US-10259789-B2
Application number	US-201716071512-A
Country	US
Kind code	B2
Filing date	Jan 23, 2017
Priority date	Jan 22, 2016
Publication date	Apr 16, 2019
Grant date	Apr 16, 2019

Abstract

4-Alkoxy-3-hydroxypicolinic acids may be conveniently prepared from 4,6-dibromo-3-hydroxypicolinonitrile in a series of chemical steps selected from bromo substitution, nitrile hydrolysis and halogen reduction that are conducted as a single pot process. 4,6-Dibromo-3-hydroxypicolinonitrile may be prepared from furfural in a series of chemical steps selected from cyano-amination, amine salt formation and bromination-rearrangement. 4-Alkoxy-3-acetoxypicolinic acids may be conveniently prepared from 4-alkoxy-3-hydroxypicolinic acids by treatment with acetic anhydride.

First claim

What is claimed is:

1. A process for the preparation of a compound of Formula H

wherein R 1 is a C 1 -C 3 alkyl;
from a compound of Formula A

which comprises the following steps:
a) creating a mixture containing the compound of Formula A and an acetylating agent; and
b) isolating the compound of Formula H from the mixture.

2. The process of claim 1 wherein the acetylating agent is selected from acetic anhydride and acetyl chloride.

3. A compound of formula

wherein R 1 is a C 1 -C 3 alkyl.

Assignees

• Dow Agrosciences Llc

Inventors

• Whiteker Gregory T
• Borromeo Peter
• Li Fangzheng
• Roth Gary

Classifications

• C07D213/803

  Processes of preparation · CPC title

• C07D213/79 Primary

  Acids; Esters · CPC title