Phosphorus oxychloride → 6-Chloro-2-methylpyrimidin-4-amine

Temperature

20 °C

150 g (1.2 mol) of anhydrous 2-methyl-4-amino6-hydroxypyrimidine are added little by little, with good stirring, to 720 ml of phosphorus oxychloride. The mixture is refluxed gently for 5 hours. A yellow solution is obtained. After cooling to 20° C., the precipitate formed is drained. An oily residue is recovered by evaporating the filtrate almost to dryness. This oily residue is poured, little by little, onto 500 g of ice, with stirring and while cooling the vessel in ice. The precipitate is introduced little by little into the solution obtained after some time. The addition is exothermic and the mixture must be cooled well in an ice bath. All of the solid dissolves. The solution is cooled to 0° C. and is rendered alkaline to pH 8 by the addition of 20% ammonia (850 ml). The formation becomes very thick. The solid is drained and washed on the filter with 100 ml of 10% aqueous sodium chloride solution and then with 200 ml of water. 144.2 g of crude product are obtained, which are recrystallised from acetonitrile. 97 g (0.676 mol) of pure product having a melting point of 191° C. are recovered. The yield of recrystallised product is 56.3%.

1. temperatureThe mixture is refluxed gently for 5 hours
2. customA yellow solution is obtained
3. customthe precipitate formed
4. customAn oily residue is recovered
5. customby evaporating the filtrate almost to dryness
6. additionThis oily residue is poured
7. temperaturewhile cooling the vessel in ice
8. additionThe precipitate is introduced little by little into the solution
9. customobtained after some time
10. additionThe addition
11. temperaturethe mixture must be cooled well in an ice bath
12. dissolutionAll of the solid dissolves
13. temperatureThe solution is cooled to 0° C.
14. washwashed on the
15. filtrationfilter with 100 ml of 10% aqueous sodium chloride solution

ORD record

ord-3a9cef93cf0c4f04a638582e8aa4f75e

Source dataset

uspto-grants-1995_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05438058