Process for synthesis of 2-amino-5-chloro-N-,3-dimethylbenzamide
Described herein are novel methods of synthesizing 2-amino-5-chloro-N,3-dimethylbenzamide. Compounds prepared by the methods disclosed herein are useful for preparation of certain anthranilamide compounds that are of interest as insecticides, such as, for example, the insecticides chlorantraniliprole and cyantraniliprole.
1. A method of preparing a compound of Formula VI, wherein
each of R 7 -R 10 is independently selected from hydrogen, halogen, halogenated C 1 -C 5 alkyl, and C 1 -C 5 alkyl;
wherein at least one of R 7 -R 10 is a halogen; and
wherein R 11 is selected from branched C 1 -C 10 alkyl and unbranched C 1 -C 10 alkyl, the method comprising
I) forming a mixture comprising
A) a compound of Formula V, wherein
each of R 7 -R 10 is independently selected from hydrogen, halogen, halogenated C 1 -C 5 alkyl, and C 1 -C 5 alkyl;
wherein at least one of R 7 -R 10 is a halogen; and
wherein the compound of Formula V is prepared according to a method comprising
i) forming a first mixture comprising
a) a compound of Formula III, wherein
each of R 1 -R 4 is independently selected from hydrogen, halogen, and C 1 -C 5 alkyl;
b) a solvent; and
c) a halogenation reagent;
ii) reacting the first mixture;
iii) adding an oxidation agent to the reacted first mixture in the presence of a catalyst to form a further mixture; and
iv) reacting the third mixture;
B) an alkylamine; and
C) a solvent; and
II) reacting the mixture.
2. The method of claim 1 , wherein the method step II) of reacting the mixture occurs at a reaction temperature in the range of about 0° C. to about 100° C.
3. The method of claim 1 , wherein the solvent b) is selected from acetonitrile, dichloroethane, toluene, chlorobenzene, xylene, acetic acid, acetic anhydride, propionic acid, butyric acid, and combinations thereof.
4. The method of claim 1 , wherein the halogenation reagent is selected from a chlorination reagent, a bromination reagent, an iodination reagent, and combinations thereof.
5. The method of claim 1 , wherein the method step ii) of reacting the first mixture occurs at a reaction temperature in the range of about 20° C. to about 140° C.
6. The method of claim 1 , wherein the oxidation agent is selected from oxygen, chlorine, sodium hypochlorite, chromium trioxide, 3-chloroperoxybenzoic acid, hydrogen peroxide, peroxyacetic acid, potassium peroxymonosulfate, potassium permanganate, and combinations thereof.
7. The method of claim 1 , wherein the catalyst is selected from sulfuric acid, hydrogen chloride, nitric acid, and combinations thereof.
8. The method of claim 1 , wherein the method step iv) of reacting the further mixture occurs at a reaction temperature in the range of about 20° C. to about 100° C.
9. The method of claim 1 , wherein the compound of Formula III is prepared according to a method comprising
I) forming a mixture comprising
A) a compound of Formula II, wherein
each of R 1 -R 5 is independently selected from hydrogen, halogen, and C 1 -C 5 alkyl; and
wherein the compound of Formula II is prepared according to a method comprising
i) forming a mixture comprising
a) a compound of Formula I, wherein
each of R 1 -R 5 is independently selected from hydrogen, halogen, and C 1 -C 5 alkyl;
b) chloral hydrate;
c) a hydroxylamine derivative;
d) a solvent;
e) an inorganic salt; and
f) an acid; and
ii) reacting the mixture; and
B) an acid; and
II) reacting the mixture.
10. A method of preparing a compound of Formula VI, wherein
each of R 7 -R 10 is independently selected from hydrogen, halogen, halogenated C 1 -C 5 alkyl, and C 1 -C 5 alkyl;
wherein at least one of R 7 -R 10 is a halogen; and
wherein R 11 is selected from branched C 1 -C 10 alkyl and unbranched C 1 -C 10 alkyl, the method comprising
I) forming a mixture comprising
A) a compound of Formula V, wherein
each of R 7 -R 10 is independently selected from hydrogen, halogen, halogenated C 1 -C 5 alkyl, and C 1 -C 5 alkyl;
wherein at least one of R 7 -R 10 is a halogen; and
wherein the compound of Formula V is prepared according to a method comprising
i) forming a mixture comprising
a) a compound of Formula IV, wherein
each of R 7 -R 10 is independently selected from hydrogen, halogen, halogenated C 1 -C 5 alkyl, and C 1 -C 5 alkyl; and
wherein at least one of R 7 -R 10 is a halogen;
b) an oxidation agent;
c) a solvent; and
d) a catalyst; and
ii) reacting the mixture;
B) an alkylamine; and
C) a solvent; and
II) reacting the mixture.
11. The method of claim 10 , wherein the alkylamine comprises a functional group selected from branched C 1 -C 10 alkyl and unbranched C 1 -C 10 alkyl.
12. The method of claim 10 , wherein the solvent C) is selected from acetonitrile, dichloroethane, toluene, chlorobenzene, xylene, methanol, ethanol, isopropanol, ethyl acetate, isopropyl acetate, and combinations thereof.
13. The method of claim 10 , wherein the method step II) of reacting the mixture occurs at a reaction temperature in the range of about 0° C. to about 100° C.
14. The method of claim 10 , wherein the oxidation agent is selected from oxygen, chlorine, sodium hypochlorite, chromium trioxide, 3-chloroperoxybenzoic acid, hydrogen peroxide, peroxyacetic acid, potassium peroxymonosulfate, potassium permanganate, and combinations thereof.
15. The method of claim 10 , wherein the catalyst is selected from sulfuric acid, hydrogen chloride, nitric acid, and combinations thereof.
16. The method of claim 1 , wherein step iii) comprises introducing a second mixture to the first mixture to form the further mixture, the second mixture comprising d) the oxidation agent and e) the catalyst.
17. The method of claim 1 , wherein the method to prepare the compound of Formula V is a single-pot method.