Process for the preparation of 4-alkoxy-3-hydroxypicolinic acids
View Patent ↗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-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.
1. A compound selected from the group consisting of:
wherein R 1 is a C 1 -C 3 alkyl;
wherein R 1 is a C 1 -C 3 alkyl; and
wherein R 1 is a C 2 -C 3 alkyl.
2. The compound of claim 1 , wherein the compound is:
3. The compound of claim 1 , wherein the compound is:
4. The compound of claim 1 , wherein the compound is:
wherein R 1 is a C 1 -C 3 alkyl.
5. The compound of claim 4 , wherein R 1 is methyl.
6. The compound of claim 1 , wherein the compound is:
wherein R 1 is a C 1 -C 3 alkyl.
7. The compound of claim 6 , wherein R 1 is methyl.
8. The compound of claim 1 , wherein the compound is:
wherein R 1 is a C 2 -C 3 alkyl.
9. The compound of claim 8 , wherein the compound is:
wherein R 1 is C 3 alkyl.