反应详情

At 0° C. a solution of diethyl 2-(p-tolyl)-malonate (14.2 g) in methanol (50 ml) was slowly added to a solution of sodium methylate (9.4 g) in methanol (300 ml). Upon completion of the addition the reaction mixture was allowed to warm up and formamidine hydrochloride (5.4 g) was added. The mixture was stirred at r.t. for 16 h. The solvent was removed under reduced pressure and the remaining residue was treated with 2 N hydrochloric acid (150 ml). The suspension was stirred for 0.5 h. At 0–5° C., the pH was carefully adjusted to 4 using 10 N sodium hydroxide solution. The precipitate was collected, washed with cold water, isopropanol, and diethyl ether and dried under high vacuum at 65° C. to give 4,6-dihydroxy-5-(p-tolyl)-pyrimidine (11.2 g) (or a tautomer) as a white powder.

1. additionUpon completion of the addition the reaction mixture
2. temperatureto warm up
3. customThe solvent was removed under reduced pressure
4. additionthe remaining residue was treated with 2 N hydrochloric acid (150 ml)
5. stirringThe suspension was stirred for 0.5 h
6. customAt 0–5° C.
7. customThe precipitate was collected
8. washwashed with cold water, isopropanol, and diethyl ether
9. customdried under high vacuum at 65° C.