Pyrazole compound preparation method

A compound and pyrazole technology, applied in the field of preparation of pyrazole compounds, can solve the problems of low production efficiency and production cost, long reaction period, serious side reactions, etc., and achieve precise control of reaction conditions, shortened reaction time, and reduced The effect of by-product formation
CN106800535AInactive Publication Date: 2017-06-06LIANHE CHEM TECH TAIZHOU
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
LIANHE CHEM TECH TAIZHOU
Publication Date
2017-06-06
Estimated Expiration
Not applicable · inactive patent

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Abstract

The invention discloses a preparation method of a pyrazole compound which is shown as a formula III. The preparation method disclosed by the invention comprises the following step of introducing a compound which is shown as a formula I and a compound which is shown as a formula II into a micro-channel reactor through different pipelines to react to obtain the pyrazole compound, wherein reaction temperature is 10 to 60 DEG C, R1 is C1-C4 alkyl, R2 and R3 are halogen independently, and R4 is methyl or phenyl. The preparation method disclosed by the invention is performed through the micro-channel reactor, has extremely-short reaction time, accurate reaction condition control and high safety, is suitable for quickly preparing products, achieves continuous production and has low cost; furthermore, the micro-channel reactor is utilized to prepare the pyrazole compound, so that reaction region selectivity is high, target compound purity is good, and the preparation method is more suitable for large-scale industrial production.
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Description

technical field

[0001] The invention relates to the technical field of organic synthesis, in particular to a preparation method of pyrazole compounds. Background technique

[0002] As an intermediate for the synthesis of other pharmaceutical compounds, pyrazole compounds are widely used in the fields of fine chemicals, medicine, and organic synthesis.

[0003] The knorr dehydration condensation of hydrazine and 1,3-dicarbonyl compounds is a convenient general method for the synthesis of pyrazole compounds. This method is simple and efficient, and is widely used in the industrial production of pyrazole compounds. However, the regioselectivity problem in the knorr reaction itself makes its side reactions unavoidable, and there are many isomers, which seriously affect the products in its industrial production. Improved yield and purity. In addition, in industrial production, due to the large amount of heat released by the reaction system during the reaction process, local une...

Claims

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