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US 8,273,904 B2Granted
Method for preparing 4-aminobut-2-enolides
AssigneeBayer CropScience AG
InventorsNorbert Lui, Jens-Dietmar Heinrich
Life of this patent
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Abstract
Process for preparing 2,2-difluoroethylamine derivatives, wherein compounds of the general formula (IV) are reduced to the corresponding 2,2-difluoroethylamine derivatives of the general formula (III), where the A radical is as defined in the description:
Claims16
A process for preparing a 4-aminobut-2-enolide compound of formula (I)
- comprising reacting a compound of formula (II)
- with an amine of formula (III)
- where
- R1 is hydrogen, alkyl, fluoroalkyl, alkenyl, fluoroalkenyl, alkynyl, cycloalkyl, cycloalkylalkyl, fluorocycloalkyl, alkoxy, alkoxyalkyl, fluorocycloalkylalkyl or arylalkyl;
- R2 is alkyl, aryl or arylalkyl;
- Z is hydrogen, an alkali metal or an alkaline earth metal;
- A is pyrid-2-yl or pyrid-4-yl, or is pyrid-3-yl which is optionally 6-substituted by fluorine, chlorine, bromine, methyl, trifluoromethyl or trifluoromethoxy, or is
- in which
- X is halogen, alkyl or fluoroalkyl, and
- Y is halogen, alkyl, fluoroalkyl, or fluoroalkoxy.
7 more elements
A process for preparing a compound of formula (V)
- comprising reacting a compound of formula (IV)
- with an alkyl chloro acetate of formula (VI)
- where
- R3 is alkyl, with the exception of ethyl, or cycloalkyl;
- R4 is alkyl, cycloalkyl, fluoroalkyl, aryl or arylalkyl.
2 more elements
Dependencies are inferred from the claim text.