Preparation of halogenated di-substituted benzylamines, particularly halogenated dialkylbenzylamines

Patent metadata

Field	Value
Publication number	US-9670135-B2
Application number	US-201415103110-A
Country	US
Kind code	B2
Filing date	Dec 8, 2014
Priority date	Dec 11, 2013
Publication date	Jun 6, 2017
Grant date	Jun 6, 2017

Abstract

The present invention relates to a novel process for preparing halogenated di-substituted benzylamines, particularly halogenated dialkylbenzylamines.

First claim

The invention claimed is:

1. Process for preparing a compound of formula (I)

where
R 1 is hydrogen, C 1 -C 8 -alkyl, C 2 -C 6 -alkenyl, C 3 -C 6 -cycloalkyl, C 1 -C 8 -alkoxy, C 1 -C 6 -alkoxy-C 2 -C 6 -alkenyl, phenyl, or benzyl;
R 2 , R 3 are each independently C 1 -C 8 -alkyl, aryl, heteroaryl, C 2 -C 6 -alkenyl, C 3 -C 8 -cycloalkyl, C 1 -C 6 -alkoxy, C 1 -C 6 -haloalkyl, or C 1 -C 6 -haloalkoxy;
X is chlorine or bromine, and
n is 0, 1, 2, 3 or 4;
comprising initially charging as reaction medium an alkali metal hydroxide in a concentration of from 20% to 50% by weight,
subsequently first A) reacting the compounds (II) and (III) in the reaction medium

where
R 1 , R 2 , R 3 and X are as defined above and
Y is chlorine, bromine, iodine, an alkylsulphonate (—OSO 2 -alkyl, preferably —OSO 2 CH 3 , —OSO 2 CF 3 ) or an arylsulphonate (—OSO 2 -aryl);
in a molar ratio of from 0.9 to 2.5 and
B adding to the reaction mixture in from 0 to 9 mol of water based on 1 mol of the compound of formula (III), and
subsequently removing the aqueous phase from the product.

2. Process according to claim 1 , wherein A) is carried out in the absence of an organic solvent.

3. Process according to claim 1 , wherein A) and B) are carried out in the absence of an organic solvent.

4. Process according to claim 1 , wherein the reaction temperature is between −20° C. and 70° C.

5. Process according to claim 1 , wherein the alkali metal hydroxide is sodium hydroxide.

6. Process according to claim 1 , wherein on completion of the addition of the compounds of formulae (II) and (III) in A) the mixture is post-reacted for 1 to 24 h.

7. Process according to claim 1 , wherein B) is followed by a purification C), wherein an organic solvent is added to the reaction mixture in a molar ratio of solvent to crude product of from 1:1 to 1:50.

8. Process according to claim 7 , wherein the pH of the reaction medium is adjusted to a value (RT) between 0 and 2 by addition of mineral acid.

9. Process according to claim 7 , comprising removing an organic phase, wherein an aqueous phase is admixed with an organic solvent and the molar ratio between solvent and crude product is from 10:1 to 1:50 and the pH is adjusted to a value (RT) between 11 and 14 with a base and the aqueous phase is removed.

10. Process according to claim 1 , comprising D) distillative removal of residual water, any residual amounts of organic solvent and residual amounts of the compound of formula (II).

11. Process according to claim 10 , comprising only A), B) and D).

12. Process according to claim 10 , comprising A), B), C) and D) wherein C) comprises adding an organic solvent to the reaction mixture in a molar ration of solvent to crude product of from 1:1:50.

13. Process according to claim 1 , wherein 1 to 5 mole of water are added in B).

14. Process according to claim 1 , which provides a yield of the compound of formula (I) of not less than 95%.

15. Process according to claim 1 , wherein R1 is hydrogen, R2 and R3 are independently methyl or ethyl, X and Y are chlorine, and n is zero.

16. Process according to claim 1 , wherein the molar ratio in A is 1 to 2.

17. Process according to claim 1 , wherein the alkali metal hydroxide is present in an at least about equimolar amount based on the amount of compounds (III).

18. Process according to claim 1 , wherein the molar ratio of alkali metal hydroxide to compounds (III) is approximately 1.05 to 1.07.

19. Process according to claim 1 comprising initially charging as reaction medium an alkali metal hydroxide in a concentration of from 25% to 45% by weight.

20. Process according to claim 1 comprising initially charging as reaction medium an alkali metal hydroxide in a concentration of from 30% to 40% by weight.

Assignees

• Bayer Cropscience Ag

Inventors

• Seeba Johann
• Schlegel Günter
• Littmann Martin
• Warsitz Rafael
• Ford Mark James

Classifications

• C07C211/29

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

• C07C209/04 Primary

  by substitution of functional groups by amino groups · CPC title

• C07C209/08 Primary

  with formation of amino groups bound to acyclic carbon atoms or to carbon atoms of rings other than six-membered aromatic rings · CPC title

• C07C209/84

  Purification · CPC title

• C07C209/14

  by substitution of hydroxy groups or of etherified or esterified hydroxy groups · CPC title