2,4-Diamino-6-hydroxy-5-nitropyrimidine

Red Rose Solid

Dissolve 126 g of diaminopyrimidine730 g of the above batch of filtrate, stirring, temperature control 30 ~ 35 °C, Add 20g of concentrated sulfuric acid, The mass concentration is 98percent.After the dropwise addition, 68.5 g (1.01 mol) of 93percent fuming nitric acid was continuously added dropwise at 30 to 35°C.After dripping, continue the incubation for 2 hours.After the reaction is completed, cool and crystallize to -5~0°C and filter.About 730 g of brownish red filtrate was obtained as the next batch of reaction solvent.The cake was washed with 100 mL of dichloromethane, 200mL drinking water washing, draining, 225 g (of 165 g) was obtained as a tan-yellow-brown red solid, i.e. a nitropyrimidine (MW 171.11) wet product.HPLC purity 98.7percent, measured as diaminopyrimidine, The yield was 96.4percent.150 g of ammonia-containing alcohol recovered in the previous batch and 40 g of 27% aqueous ammonia were placed in a 500-mL autoclave.40.9 g of the nitropyrimidine wet product prepared in and 1.0 g of Raney nickel catalyst were added at room temperature.After the feed was completed, it was immediately replaced with high-purity nitrogen 3 times.Then replace it with high-purity hydrogen 3 times and stir it.6 g of liquid ammonia was introduced at room temperature.Through ammonia, pressurize with hydrogen to 0.6MPa, Adjust the speed to 800 rpm/minuteThe mixture was heated to 60C and hydrogenated.When the pressure in the kettle falls to 0.4MPa, the temperature is controlled to 70~80C.Hydrogen holding pressure 0.75 ~ 0.80MPa reaction for 6 hours.After the hydrogenation is over, the excess hydrogen in the kettle is drained.Replace with high-purity nitrogen 3 times; after standing for 15 minutes, Nitrogen-fed slurry was poured into a nitrogen-protected pear-shaped bottle.Raney Nickel stays at the bottom of the kettle and applies it directly to the next batch of reactions.After finishing the pressing, concentrate and recover alcohol at normal pressure.When the internal temperature reaches 80C and no liquid distills out, it is instead concentrated under reduced pressure.About 155 g of distillate was obtained, which is ammonia-containing alcohol and can be applied directly to the next batch.When the residue in the bottle is about 50 g, the concentration is stopped, under nitrogen protection, cooling and crystallization to 5 ~ 0 C, pressure filtration to dry, filterThe cake was dried under vacuum to give 26.0 g of a pale yellow powder which was a triaminopyrimidine.The HPLC purity was 98.7%, and the nitropyrimidine active ingredient had a molar yield of 95.2%.Dissolve 126 g of diaminopyrimidine730 g of the above batch of filtrate, stirring, temperature control 30 ~ 35 C, Add 20g of concentrated sulfuric acid, The mass concentration is 98%.After the dropwise addition, 68.5 g (1.01 mol) of 93% fuming nitric acid was continuously added dropwise at 30 to 35C.After dripping, continue the incubation for 2 hours.After the reaction is completed, cool and crystallize to -5~0C and filter.About 730 g of brownish red filtrate was obtained as the next batch of reaction solvent.The cake was washed with 100 mL of dichloromethane, 200mL drinking water washing, draining, 225 g (of 165 g) was obtained as a tan-yellow-brown red solid, i.e. a nitropyrimidine (MW 171.11) wet product.HPLC purity 98.7%, measured as diaminopyrimidine, The yield was 96.4%.