Process for preparing 2-dihaloacyl-3-aminoacrylic acid derivatives

1. Process for preparing a 2-dihaloacyl-3-aminoacrylic ester of formula (I)

in which

R 1 and R 2 are each independently selected from C 1-12 -alkyl radicals, C 5-18 -aryl, C 7-19 -alkylaryl and C 7-9 -arylalkyl radicals, or

R 1 and R 2 , together with the nitrogen atom to which they are bonded, may form a 5- to 6-membered ring which may optionally contain one or two further heteroatoms selected from 0, S and an SO 2 group,

Y is selected from (C═O)OR 3 , CN and (C═O)NR 4 R 5 , where R 3 , R 4 and R 5 are each independently selected from C 1-12 -alkyl radicals, C 5-18 -aryl, C 7-19 -alkylaryl and C 7-19 -arylalkyl radicals, and R 4 and R 5 , together with the nitrogen atom to which they are bonded and/or further atoms which are selected from C, N, O and S, may form a five- or six-membered ring which may be substituted by C 1-6 -alkyl radicals; and

X 1 and X 2 are each independently fluorine, chlorine, bromine and iodine,

said process comprising reacting an acid fluoride of formula (II)

with a 3-aminoacrylic acid derivative of formula (III)

wherein the reaction is effected in the absence of a base.

2. Process according to claim 1 , wherein

R 1 and R 2 are each independently selected from methyl, ethyl, n-propyl and isopropyl, or

R 1 and R 2 , together with the nitrogen atom to which they are bonded, form a piperidinyl or pyrrolidinyl ring,

Y is selected from (C═O)OR 3 where R 3 is selected from methyl, ethyl, n-propyl and isopropyl,

X 1 and X 2 are each independently selected from fluorine, chlorine and bromine.

3. Process according to claim 1 , wherein

R 1 and R 2 are each methyl,

Y is (C═O)OC 2 H 5 and

X 1 and X 2 are both fluorine.

4. Process according to claim 1 , wherein the 3-aminoacrylic acid derivative is selected from the group consisting of methyl 3-(N,N-dimethylamino)-acrylate, ethyl 3-(N,N-dimethylamino)acrylate, ethyl 3-(N,N-diethylamino)acrylate, 3-(N,N-dimethylamino)acrylonitrile, N,N-dimethyl-3-(N,N-dimethylamino)acrylamide and N,N-diethyl-3-(N,N-dimethylamino)acrylamide.

5. Process according to claim 1 , wherein the reaction is effected in an organic solvent.

6. Process according to claim 2 , wherein

R 1 and R 2 are each methyl,

Y is (C═O)OC 2 H 5 and

X 1 and X 2 are both fluorine.

7. Process according to claim 2 , wherein the 3 aminoacrylic acid derivative is selected from the group consisting of methyl 3-(N,N-dimethylamino)-acrylate, ethyl 3-(N,N-dimethylamino)acrylate, ethyl 3-(N,N-diethylamino)acrylate, 3-(N,N-dimethylamino)acrylonitrile, N,N-dimethyl-3-(N,N-dimethylamino)acrylamide and N,N-diethyl-3-(N,N-dimethylamino)acrylamide.

8. Process according to claim 3 , wherein the 3 aminoacrylic acid derivative is selected from the group consisting of methyl 3-(N,N-dimethylamino)-acrylate, ethyl 3-(N,N-dimethylamino)acrylate, ethyl 3-(N,N-diethylamino)acrylate, 3-(N,N-dimethylamino)acrylonitrile, N,N-dimethyl-3-(N,N-dimethylamino)acrylamide and N,N-diethyl-3-(N,N-dimethylamino)acrylamide.

9. Process according to claim 2 wherein the reaction is effected in an organic solvent.

10. Process according to claim 3 wherein the reaction is effected in an organic solvent.

11. Process according to claim 4 wherein the reaction is effected in an organic solvent.

12. Process according to claim 1 , wherein the 3-aminoacrylic acid derivative is ethyl 3-(N,N-dimethylamino)-acrylate.