Process for the preparation of phenylmalonic acid dinitriles

Patent metadata

Field	Value
Publication number	US-10759742-B2
Application number	US-201716319304-A
Country	US
Kind code	B2
Filing date	Jul 20, 2017
Priority date	Jul 22, 2016
Publication date	Sep 1, 2020
Grant date	Sep 1, 2020

Abstract

Process for the preparation of a compound of Formula (I), the process comprising the reaction of a compound of Formula (II) with malononitrile in the presence of a base and a palladium catalyst, Formula (II) wherein X, Y and Z, independently of each other, represent fluoro, chloro or C 1-4 alkyl; and L is a leaving group; with the proviso that 1 or 2 of X and Y are, independently of each other, fluoro or chloro.

First claim

The invention claimed is:

1. A process comprising:
reacting a compound of Formula (I)

wherein
X, Y and Z, independently of each other, represent fluoro, chloro or C 1-4 alkyl, and with the proviso that 1 or 2 of X and Y are, independently of each other, fluoro or chloro;

with an acid in the presence of water, and toluene or xylene to form a compound of Formula (III)

2. The process according to claim 1 , wherein the reacting of the compound of Formula (I) to the compound of Formula (III) is carried out at 120 to 155° C.

3. The process according to claim 1 , wherein the acid is sulphuric acid.

4. The process according to claim 1 , wherein X is methyl, Y is chloro, and Z is methyl.

5. The process according to claim 1 , further comprising reacting a compound of Formula (II)

wherein
X, Y and Z, independently of each other, represent fluoro, chloro or C 1-4 alkyl; and
L is a leaving group;
with the proviso that 1 or 2 of X and Y are, independently of each other, fluoro or chloro, with malononitrile in the presence of a base and a palladium catalyst to form the compound of Formula (I):

6. The process according to claim 5 , wherein the reacting the compound of Formula (II) to form the compound of Formula (I) comprises:
(i) reacting malononitrile with the base forms a malononitrile anion ([NCCHCN] − ); and
(ii) reacting the compound of Formula (II) with the malononitrile anion of step (i) in the presence of the palladium catalyst forms the compound of Formula (I).

7. The process according to claim 5 , wherein X is methyl, Y is chloro and Z is methyl.

8. The process according to claim 7 , wherein L is bromo.

9. The process according to claim 5 , wherein the base is an alkali metal hydroxide.

10. The process according to claim 5 , wherein the palladium catalyst is prepared in situ from palladium (lI) or palladium (0) compounds by complexing with phosphine ligands.

11. The process according to claim 5 , wherein the reacting the compound of Formula (II) to form the compound of Formula (I) is carried out in the presence of a dipolar solvent.

12. The process according to claim 5 , wherein the reacting the compound of Formula (II) to form the compound of Formula (I) is carried out at 110 to 150° C.

13. The process according to claim 9 , wherein the alkali metal hydroxide is sodium hydroxide.

14. The process according to claim 11 , wherein the dipolar aprotic solvent is N-methyl-2-pyrrolidone.

15. The process according to claim 6 , wherein the reacting of malononitrile with a base to form a malononitrile anion ([NCCHCN] − ) is done at between 10-15° C.

16. A process comprising:
charging a container having solid sodium hydroxide with an inert atmosphere;
dropping 1-methyl-2-pyrrolidone into the container and cooling to 10-15° C. while stirring;
dropping malononitrile into the container while maintaining a temperature of 10-15° C.;
distilling off the 1-methyl-2-pyrrolidone;
adding 2-bromo-5-chloro-1,3-dimethyl-benzene to the container;
adding palladium (II) chloride, triphenylphosphine, and 1-methyl-2-pyrrolidone to the container to react the 2-bromo-5-chloro-1,3-dimethyl-benzene to 2-(4-chloro-2,6-dimethyl-phenyl)propanedinitrile; and
recrystallizing the 2-(4-chloro-2,6-dimethyl-phenyl)propanedinitrile in iso-propanol.

Assignees

• Syngenta Participations Ag

Inventors

• Zeller Martin
• Fedou Nicolas

Classifications

• C07C255/35 Primary

  the carbon skeleton being further substituted by halogen atoms, or by nitro or nitroso groups · CPC title

• C07C255/33

  with cyano groups linked to the six-membered aromatic ring, or to the condensed ring system containing that ring, by saturated carbon chains · CPC title

• C07C253/30 Primary

  by reactions not involving the formation of cyano groups · CPC title

• C07C53/134

  monocyclic · CPC title

• C07C51/08

  from nitriles · CPC title