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.
本发明涉及一种制备式(I)的2-(氨甲亚基)-4,4-二卤-3-氧代丁酸酯的方法,其中R1、R2、R3为C1-C6烷基、C1-C6卤代烷基、C2-C6烯基、C3-C10环烷基或苄基,和/或R2与R3以及它们所连接的氮原子是杂环基,其中相应的3-氨基丙烯酸酯在至少一种碱金属或碱土金属氟化物的存在下与卤代乙酰氟反应;以及将卤代2-(氨甲亚基)-3-氧代丁酸酯式(I)进一步转化为卤代甲基取代的吡唑-4-基羧酸和它们的酯。