N-(2-CHLOROMETHYL-1-METHYL-1H-BENZIMIDAZOLE-5-ACYL)-N-(PYRIDINE-2-YL)-3-AMINOPROPANOIC ACID ETHYL ESTER PREPARATION METHOD
申请人:ABA Chemicals Corporation
公开号:EP3153509A1
公开(公告)日:2017-04-12
The Invention discloses a method for preparing a Dabigatran etexilate intermediate. The process of the method is as follows: a) taking 3-amino-4-methylamino benzoic acid as the raw material, synthesizing 2-methyl chloride-1-methyl-1H-benzimidazole-5-carboxylic acid through cyclization reaction with chloroacetyl chloride; b) the 2-methyl chloride-1-methyl-1H-benzimidazole-5-carboxylic acid generates 2-methyl chloride-1-methyl-1H-benzimidazole-5 formyl chloride under the action of oxalyl chloride; c) the 2-methyl chloride-1-methyl-1H-benzimidazole-5-formyl chloride generates N-(2-methyl chloride-1-methyl-1H-benzimidazole-5-acyl)-N-(pyridine-2-yl)-3-aminopropionic acid ethyl ester through condensation reaction with 3-(pyridine-2-yl) aminopropionic acid ethyl ester. The synthetic route has not been reported ever before; moreover, with cheap and widely available raw materials, simple unit operation and low requirement for equipment, the method is suitable for industrialized mass production.
本发明公开了一种制备达比加群酯中间体的方法。该方法的工艺流程如下:a) 以 3-氨基-4-甲基氨基苯甲酸为原料,通过与氯乙酰氯的环化反应合成 2-甲基氯-1-甲基-1H-苯并咪唑-5-羧酸; b) 2-甲基氯-1-甲基-1H-苯并咪唑-5-羧酸在草酰氯的作用下生成 2-甲基氯-1-甲基-1H-苯并咪唑-5-甲酰氯;c) 2-甲基-1-甲基-1H-苯并咪唑-5-甲酰氯与 3-(吡啶-2-基)氨基丙酸乙酯发生缩合反应,生成 N-(2-甲基-1-甲基-1H-苯并咪唑-5-酰基)-N-(吡啶-2-基)-3-氨基丙酸乙酯。该合成路线以前从未报道过,而且原料便宜、来源广泛、单元操作简单、设备要求低,适合工业化大规模生产。