反应详情

温度

-68 °C

5.9 g (23 mmol) of 2-anilino-4-methoxymethyl-6-cyclopropylpyrimidine, prepared from phenylguanidine and 1-cyclopropyl-4-methoxy-1,3-butanedione, are dissolved in 200 ml of dichloromethane and the solution is cooled to -68° C. 6.8 g (27 mmol) of boron tribromide are slowly added dropwise to the salmon-coloured solution within a period of half an hour, with vigorous stirring, and the cooling bath is then removed and stirring is continued for a further 2 hours at room temperature. After the addition of 150 g of ice-water, the precipitated crude product is filtered off and recrystallised from methanol using active carbon. The light-yellow crystals melt at 124°-126° C. Yield: 4.7 g (19.5 mmol; 84.7% of the theoretical yield).

1. customthe cooling bath is then removed
2. additionAfter the addition of 150 g of ice-water
3. customthe precipitated crude product
4. filtrationis filtered off
5. customrecrystallised from methanol using active carbon
6. custommelt at 124°-126° C
7. custom84.7% of the theoretical yield)