Method for synthesizing 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic acid and intermediates thereof
申请人:ZHEJIANG YONGTAI TECHNOLOGY CO., LTD.
公开号:US10556868B2
公开(公告)日:2020-02-11
The present invention relates to a method for synthesizing a compound of 3-(difluoromethyl)-1-methyl-1h-pyrazole-4-carboxylic acid, wherein including the steps of:
(A) the diethyl ester compounds represented by the following Formula IV are reacted under the action of amine, alkali and carbonyl reagents to produce the acrylic diester compound represented by the following Formula I,
wherein:
(B) the above compound represented by the Formula I is reacted with a fluoride reagent, a Lewis acid and a methyl hydrazine to form a pyrazole ring-containing diester compound represented by the Formula II,
(C) the heterocyclic-containing diester compound represented by the Formula II is reacted with a base to give 3-(difluoromethyl)-1-methyl-1h-pyrazole-4-carboxylic acid represented by the Formula III.
本发明涉及一种合成 3-(二氟甲基)-1-甲基-1h-吡唑-4-羧酸化合物的方法,其中包括以下步骤: 1:
(A) 在胺、碱和羰基试剂的作用下,使下式IV所代表的二乙酯化合物发生反应,生成下式I所代表的丙烯酸二酯化合物、
其中:
(B) 将上述式 I 所代表的化合物与氟化试剂、路易斯酸和甲基肼反应,生成式 II 所代表的含吡唑环的二酯化合物、
(C) 式 II 所代表的含杂环二酯化合物与碱反应,得到式 III 所代表的 3-(二氟甲基)-1-甲基-1h-吡唑-4-羧酸。