16019-33-3Relevant articles and documents
Process for synthesizing 2-(4,6-dichloropyrimidine-5-yl) acetaldehyde through continuous flow ozonation
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Paragraph 0032-0034; 0046-0047, (2020/08/06)
The invention discloses a process for synthesizing 2-(4,6-dichloropyrimidine-5-yl) acetaldehyde by continuous flow ozonation, which comprises the following steps: by using 5-allyl-4,6-dichloropyrimidine as a raw material, carrying out continuous flow ozonation, and carrying out sodium thiosulfate reduction to obtain the target product. The invention provides a brand-new continuous flow process forozonization synthesis of 2-(4,6-dichloropyrimidine-5-yl) acetaldehyde, which is safe, simple to operate, efficient and easy for large-scale production.
Method for preparing 4, 6-dichloropyrimidine-5-acetaldehyde
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Paragraph 0038; 0041-0043, (2019/04/26)
The invention discloses a method for preparing 4, 6-dichloropyrimidine-5-acetaldehyde, and belongs to the field of organic chemistry. According to the technical scheme, diethyl malonate is added intoan organic solvent, alkali and 2-bromomethyl-1, 3-dioxolane are added, the mixture is heated to 60-70 DEG C, reacting is carried out for 2-4 hours, after water is added, extracting is carried out by using methyl tert-butyl ether, and the methyl tert-butyl ether is evaporated to obtain a first intermediate; sodium alkoxide is added into an organic alcohol solution, formamidine acetate is added, stirring is carried out at room temperature for 30-45min, the first intermediate is added for reacting for 20-30h, the filtrate is evaporated, recrystallizing is carried out by using ethanol to obtain asecond intermediate; the second intermediate is added into a chlorination reagent, heating and refluxing are carried out for 10-15h, ice water is poured in, extracting is carried out by using ethyl acetate, the ethyl acetate is evaporated to obtain a third intermediate which is added into acidic solution for heating for 2-4h, and then cooled down to room temperature, extracting is carried out by using dichloromethane, drying is carried out by using anhydrous sodium sulfate, then the dichloromethane is evaporated to dryness, and petroleum ether is recrystallized to obtain the 4, 6-dichloropyrimidine-5-acetaldehyde. According to the invention, the risk of explosion is reduced, the requirement of experimental equipment is low, and the requirement of batch production is met.
An improved synthesis of 4-chloro-7H-pyrrolo[2,3-d]pyrimidine
Zhang, Yu-Liu,Xu, Cheng-Tao,Liu, Ting,Zhu, Yong,Luo, Yu
, p. 638 - 642 (2018/08/17)
[Figure not available: see fulltext.] An improved seven-step synthesis of 4-chloro-7H-pyrrolo[2,3-d]pyrimidine from dimethyl malonate with 31% overall yield is described. The procedure is operationally simple and practical for the synthesis of the 4-chloro-7H-pyrrolo[2,3-d]pyrimidine building block.