The present invention discloses a process for preparing 5-fluorooxindole represented by the formula (3):
which comprises (A) a first step of cyclizing 2-(5-fluoro-2-nitrophenyl)malonic acid diester represented by the formula (1) :
wherein R1 and R2 may be the same or different from each other and each represents a group which does not participate in the reaction,
under reductive conditions to form 5-fluorooxindole-3-carboxylic acid ester represented by the formula (2):
wherein R1 has he same meaning as defined above, and
(B) then, a second step of decarboxylating the 5-fluorooxindole-3-carboxylic acid ester,
and a process for preparing its synthetic intermediates.
本发明公开了一种制备式(3)所代表的
5-氟吲哚的工艺:
其中包括 (A) 第一步,环化式 (1) 所代表的 2-(5-
氟-2-
硝基苯基)
丙二酸二酯:
其中 R1 和 R2 可以相同或不同,各自代表不参与反应的基团、
在还原条件下生成式(2)代表的
5-氟吲哚-3-
羧酸酯:
其中 R1 的含义与上述定义相同,以及
(B) 然后,对
5-氟吲哚-3-
羧酸酯进行第二步脱羧、
以及制备其合成中间体的工艺。