反应详情

A mixture of 6 g of 10% Pd/C and 60 g (370 mmol) of 2-amino-4-(trifluoromethyl)pyrimidine dissolved in 80 mL of water, 250 mL of isopropanol and 24 mL (370 mmol) of methanesulfonic acid is hydrogenated at 5 bar, at 40° C., for 5 hours in an autoclave. The resulting mixture is then filtered and rinsed with isopropanol and with water. The filtrate is then concentrated under reduced pressure and the residue obtained is dried under vacuum to give 93.5 g of 4-trifluoromethyl-1,4,5,6-tetrahydropyrimidin-2-ylamine methanesulfonate in the form of a white solid. The white solid is dissolved in 250 mL of methyl isobutyl ketone. 100 mL of 10 N sodium hydroxide are then added. The mixture is stirred at room temperature for 15 minutes. The phases are separated by settling and the aqueous phase is re-extracted with methyl isobutyl ketone. The organic phases are combined and then evaporated under vacuum. 59.50 g of 4-trifluoromethyl-1,4,5,6-tetrahydropyrimidin-2-ylamine are thus obtained, the characteristics of which are as follows:

1. filtrationThe resulting mixture is then filtered
2. washrinsed with isopropanol and with water
3. concentrationThe filtrate is then concentrated under reduced pressure
4. customthe residue obtained
5. customis dried under vacuum