Method for the production of halogen-substituted 2-(aminomethylidene)-3-oxobutyric acid esters
申请人:Zierke Thomas
公开号:US08586750B2
公开(公告)日:2013-11-19
The present invention relates to a process for preparing 2-(aminomethylidene)-4,4-dihalo-3-oxobutyric esters of the formula (I),
wherein R1, R2, R3 are C1-C6-alkyl, C1-C6-haloalkyl, C2-C6-alkenyl, C3-C10-cycloalkyl or benzyl, and/or R2 together with R3 and the nitrogen atom to which the two radicals are attached are a heterocyclic radical, in which a corresponding 3-aminoacrylic ester is reacted with a halogen-substituted acetyl fluoride in the presence of at least one alkali or alkaline earth metal fluoride; and the further conversion of halogen-substituted 2-(aminomethylidene)-3-oxobutyric esters of the formula (I) to halomethyl-substituted pyrazol-4-ylcarboxylic acids and their esters.
Method for the Production of Halogen-Substituted 2-(aminomethylidene)-3-oxobutyric Acid Esters
申请人:Zierke Thomas
公开号:US20110040096A1
公开(公告)日:2011-02-17
The present invention relates to a process for preparing 2-(aminomethylidene)-4,4-dihalo-3-oxobutyric esters of the formula (I),
wherein R
1
, R
2
, R
3
are C
1
-C
6
-alkyl, C
1
-C
6
-haloalkyl, C
2
-C
6
-alkenyl, C
3
-C
10
-cycloalkyl or benzyl, and/or R
2
together with R
3
and the nitrogen atom to which the two radicals are attached are a heterocyclic radical, in which a corresponding 3-aminoacrylic ester is reacted with a halogen-substituted acetyl fluoride in the presence of at least one alkali or alkaline earth metal fluoride; and the further conversion of halogen-substituted 2-(aminomethylidene)-3-oxobutyric esters of the formula (I) to halomethyl-substituted pyrazol-4-ylcarboxylic acids and their esters.