Process for synthesizing triazole derivative

Abstract

The invention belongs to the field of medicament processing and particularly relates to a process for synthesizing a triazole derivative. The process has the advantages that the raw materials are easily available, time consumption is low, reaction conditions are mild and yield is high. According to the technical scheme, the process comprises the following steps: adding formamide to a four-necked flask which contains a stirrer, a constant-pressure dropping funnel, a distillation device and a tail-gas absorption device; heating to a temperature of 175-190 DEG C; dropwise adding hydrazine hydrate for 0.5-2.5 hours, wherein the molar ratio of formamide to hydrazine hydrate is 1:(1.1-2); introducing the escaping ammonia into an absorption bottle filled with 20-30% H2SO4; preserving heat for 0.5-2.5 hours after finishing adding dropwise; cooling and filtering after a large amount of crystals are separated, to obtain a crude product; washing the crude product by ethyl acetate to obtain the target product which is 1H-1,2,4-triazol; calculating the yield; and measuring the melting point.

Description

Technical field: [0001] The invention belongs to the field of medicine processing, and more specifically relates to a synthesis technique of triazole derivatives. Background technique: [0002] 1H-1,2,4-triazole is an important medicine, pesticide and dye intermediate. Especially in the field of medicine, triazole pharmacophore has lower toxicity than imidazole and exhibits various biological activities, such as antifungal, antibacterial, antituberculosis, antiviral, etc. 1H-1,2,4-triazole and its derivatives have become one of the hot spots and focuses of drug research and development in recent years. [0003] At present, there are four main methods for synthesizing 1H-1,2,4-triazole: [0004] (1) Prepared by the reaction of formamide and formamide. The raw materials of this method are relatively expensive, and most of them use excess formamide as a solvent. After-treatment, formamide needs to be evaporated under reduced pressure. The operation is very complicated. If it ...

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Problems solved by technology

[0004] (1) Prepared by the reaction of formamide and formamide. The raw materials of this method are relatively expensive, and most of them use excess formamide as a solvent. After-treatment, formamide needs to be evaporated under reduced pressure. The operation is very complicated. If it is not handled properly, the yield will be greatly reduced. Rate;

[0005] (2) It is prepared from three raw materials of formic acid, hydrazine hydrate, and formamide. This method uses more raw materials, and the double-tube feeding method has strict requirements on the feeding speed, and the reaction is divided into two stages. The process is more complicated and the production cycle is longer;

[0006] (3) Feed ammonia gas into formic acid earlier to generate ammonium formate, then add hydrazine hydrate dropwise. The first step of this method is to feed ammonia gas into a two-phase reaction, the reaction conditions are harsh, the reaction time is long, and the operation is more complicated;

[0007] (4) Prepared from formamide and hydrazine hydrate, this method is simple and convenient, the yield is high, the reaction time is 4.5-5h, and it needs to stand overnight to wait for crystallization, and the production cycle is long

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