- A method for preparing 2, 4 - substituted pyrimidine
-
The invention belongs to the technical field of the synthesized compounds, in particular to a 2, 4 - substituted pyrimidine of the preparation method. The method comprises the following steps: 1) the 2 - substituted pyrimidine dissolved in tetrahydrofuran, in - 60 — - 78 °C lower dropping TMP.MgCl.LiCl, dropping 1 h after adding anhydrous zinc chloride, raising the temperature to room temperature, dropping halogen, 2 h after adding hydrochloric acid solution quenching reaction; 2) reaction of the reaction solution in order to ethyl acetate extraction, drying of the organic layer concentrated, column chromatography purification to obtain the product. The invention compared with the prior art, in order to 2 - substituted pyrimidines as raw materials can be specific selection 4 substituted, at the same time does not produce 5 substituted by-product, with good selectivity, single product, is easy to be purified, with mild reaction conditions, the reaction speed and the like.
- -
-
Paragraph 0010; 0020-0021
(2019/06/05)
-
- Highly efficient, chemoselective syntheses of 2-methoxy-4-substituted pyrimidines
-
Three 2-methoxy-4-substituted pyrimidine compounds were chemoselectively synthesized by diazotization, using 2,4-dichloropyrimidine as the starting material. In nonaqueous diazotization reaction system, halo-substituted 6 and 7 were efficiently prepared, and in aqueous medium, hydrolysis product 8 was afforded.
- Xu, Chunyan,Cheng, Chuanjie,Liu, Hongtao,Liu, Bo
-
experimental part
p. 545 - 548
(2012/06/01)
-