A post-processing method for synthesizing 4,6-dihydroxypyrimidine
A technology of dihydroxypyrimidine and hydroxypyrimidine sodium salt, which is applied in the post-treatment field of synthesizing 4,6-dihydroxypyrimidine, which can solve the problems of large energy consumption, large amount of waste water, and many impurities, so as to reduce energy consumption and improve product quality. The effect of improving the yield and product yield
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0042] (1) Add 2,900kg of methanol solution containing 30% sodium methoxide to a 10,000L reactor, then add 500kg of formamide, heat up to 55°C, then start to drop 600kg of dimethyl malonate, and control the reaction temperature at 55-60°C , after the dropwise addition, keep warm for 2 hours;
[0043] (2) Cool down to 30-35°C, add 2300kg of water, and stir for 1 hour to dissolve the sodium salt of 4,6-dihydroxypyrimidine;
[0044] (3) Add 5kg of powdered activated carbon, stir and decolorize at 40°C for 1 hour, and filter the activated carbon out of the plate frame;
[0045] (4) Add 30%wt hydrochloric acid to the filtrate filtered by the plate and frame to acidify to pH 2-3, precipitate 4,6-dihydroxypyrimidine, filter it with a centrifuge, and wash 4,6-dihydroxypyrimidine with 300kg of deionized water Pyrimidine, dried to obtain 4,6-dihydroxypyrimidine 484kg, content 99.5%, yield 95.1%;
[0046] (5) Add 15kg of 30%wt hydrochloric acid to the mother liquor obtained by the cent...
Embodiment 2
[0051] (1) Add 3000kg of methanol solution containing 30% sodium methoxide to a 10,000L reactor, then add 285kg of recovered formamide obtained in Example 1, add 215kg of purchased formamide, raise the temperature to 58°C, and then start adding 600kg of propanediol dropwise Acetate dimethyl ester, control the reaction temperature at 55-60 ° C, after the dropwise addition is completed, keep the temperature for 2 hours;
[0052] (2) Cool down to 30-35°C, add 2350kg of washing water and extracted water from Example 1, and stir for 1.5 hours to dissolve 4,6-dihydroxypyrimidine sodium salt;
[0053] (3) Add 7kg of powdered activated carbon, stir and decolorize at 30°C for 1.5 hours, and filter the activated carbon out of the plate frame;
[0054] (4) Add 25%wt hydrochloric acid to the filtrate filtered by the plate frame to acidify to pH 2-3, and precipitate 4,6-dihydroxypyrimidine, filter it with a centrifuge, and wash with 320kg of dewatered water from Example 1 4,6 -Dihydroxypy...
Embodiment 3
[0060] (1) Add 2900kg of methanol solution containing 30% sodium methoxide to a 10000L reactor, then add 287kg of recovered formamide obtained in Example 2, add 213kg of purchased formamide, raise the temperature to 55°C, and then start adding 600kg of propanediol dropwise Acetate dimethyl ester, control the reaction temperature at 55-60 ° C, after the dropwise addition is completed, keep the temperature for 2 hours;
[0061] (2) Cool down to 30-32°C, add 2450kg of washing water and extracted water from Example 2, and stir for 2 hours to dissolve 4,6-dihydroxypyrimidine sodium salt;
[0062] (3) Add 6kg of powdered activated carbon, stir and decolorize at 20°C for 2 hours, and filter the activated carbon out of the plate frame;
[0063] (4) Add 25%wt hydrochloric acid to the filtrate filtered by the plate frame to acidify to pH 2-3, precipitate 4,6-dihydroxypyrimidine, filter it with a centrifuge, and use 320kg of dewatered water from Example 2 to wash 4,6 -dihydroxypyrimidin...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More