Method for synthesizing 5-bromopyridine-3-formaldehyde

Abstract

The invention belongs to the field of organic synthesis, and particularly relates to a method for synthesizing 5-bromopyridine-3-formaldehyde. In the method, 3,5-dibromopyridine is taken as a material, and tetramethylethylenediamine is taken as a stabilizer, so as to react with a Grignard reagent to prepare a product. The existence of tetramethylethylenediamine reduces the impurities in the product, and improves the yield; the synthesis method has a low requirement on the temperature, can be finished under the condition of 5 to 25 DEG C, saves energy consumption, and is easy to operate; in thesynthesis technology, a simple post-processing method has few steps and high yield, and is suitable for industrial production.

Description

technical field [0001] The invention belongs to the field of organic synthesis, in particular to a synthesis method of 5-bromopyridine-3-carbaldehyde. Background technique [0002] In the prior art, there are many ways to synthesize 5-bromopyridine-3-carbaldehyde; literature reports use 3,5-dibromopyridine as a raw material, and exchange it with butyl lithium bromide lithium at ultra-low temperature (-78°C) to prepare 5-bromopyridine-3-carbaldehyde -Bromopyridine-3-carbaldehyde (reference: Non-symmetrical, potentially redox non-innocent imino NHC pyridine'pincers'via azinc ion template-assisted synthesis.Simler,Thomas et al.Dalton Transactions,46(18),5955- 5964; 2017), another literature report uses 3,5-dibromopyridine as raw material, and at -15 ° C temperature, butyllithium and n-butylmagnesium chloride are combined to synthesize 5-bromopyridine-3-carbaldehyde (reference : process for preparation offfunctionalized pyridylamines from halopyridines.Hagadorn, John Robert et ...

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Problems solved by technology

[0002] In the prior art, there are many ways to synthesize 5-bromopyridine-3-carbaldehyde; literature reports use 3,5-dibromopyridine as a raw material, and exchange it with butyl lithium bromide lithium at ultra-low temperature (-78°C) to prepare 5-bromopyridine-3-carbaldehyde -Bromopyridine-3-carbaldehyde (reference: Non-symmetrical, potentially redox non-innocent imino NHC pyridine'pincers'via azinc ion template-assisted synthesis.Simler,Thomas et al.Dalton Transactions,46(18),5955- 5964; 2017), another literature report uses 3,5-dibromopyridine as raw material, and at -15 ° C temperature, butyllithium and n-butylmagnesium chloride are combined to synthesize 5-bromopyridine-3-carbaldehyde (reference : process for preparation offfunctionalized pyridylamines from halopyridines.Hagadorn, John Robert et al.U.S.Pat.Appl.Publ., 20090082573, 26Mar 2009); the above two synthetic methods can only be carried out under ultra-low temperature conditions, and the reaction conditions are harsh and difficult to industrialize; It has been reported in the literature that 5-bromo-3-methylpyridine is used as a raw material, and selenium dioxide is oxidized to synthesize 5-bromopyridine-3-carbaldehyde (reference: Preparation ofheterocyclyloxyphenoxyethyl substituted pyrimidine-2,4(1H,3H)-diones for treating HIV infections.Jorgensen, William L.and Anderson, KarenS.U.S.Pat.Appl.Publ., 20150105351, 16Apr 2015); but in the reaction process, a large amount of selenic acid derivatives are attached to the inner wall of the reactor, and post-treatment is very difficult; there is also a The synthetic method is to use 5-methyl-3-aminopyridine as a raw material, and then undergo bromination and hydrolysis twice to obtain the product (reference: Stilbene heterocycles: synthesis, antimicrobial, antioxidant and anticancer activities. Reddy, G. Chandrasekara et al

PharmaInnovation, 3(12-A), 24-30; 2015), but this method has many steps and low yield

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