反应详情

温度

-70 °C

n-Butyllithium (19.2 ml of a 2.5M solution in hexane) was added dropwise to a stirred suspension of the product of stage (a) above (5.0 g) in dry tetrahydrofuran (100 ml) under nitrogen at -70° C. The mixture was stirred at -70° C. for 20 minutes and then at 5° C. for 3 hours. It was then cooled to -70° C. and treated with 4,6-dimethoxy-2-methylsulfonylpyrimidine (5.42 g), and the mixture was stirred at -70° C. for 1 hour, then at room temperature overnight. Saturated ammonium chloride solution (500 ml) was added, and the mixture was extracted with ethyl acetate (2×100 ml). The combined extracts were washed with saturated sodium chloride solution (50 ml), dried and evaporated to give an orange oil which was triturated with hexane to give 5.35 g of the desired product as a pale yellow solid, mp 89°-92° C.

1. waitat 5° C. for 3 hours
2. temperatureIt was then cooled to -70° C.
3. stirringthe mixture was stirred at -70° C. for 1 hour
4. customat room temperature
5. customovernight
6. extractionthe mixture was extracted with ethyl acetate (2×100 ml)
7. washThe combined extracts were washed with saturated sodium chloride solution (50 ml)
8. customdried
9. customevaporated
10. customto give an orange oil which
11. customwas triturated with hexane