反应详情

To a solution of 3-(2,4-dichloro-phenyl)-2,6-dimethyl-pyrazolo[5,1-b]oxazole (Intermediate HE) (0.755 g, 2.69 mmol) in DMF (10 ml) is added NBS (0.502 g, 2.82 mmol). The reaction is stirred at RT for 30 mins and then partitioned between Na2CO3 and EtOAc. The mixture is extracted with EtOAc (×2) and the combined organic phases are dried over Na2SO4, filtered and evaporated to dryness under reduced pressure. This resulting solid is recrystallised from hot EtOAc/iso-hexane to yield the title compound. MS: m/z 360.99 [M+H]+

1. custompartitioned between Na2CO3 and EtOAc
2. extractionThe mixture is extracted with EtOAc (×2)
3. dry with materialthe combined organic phases are dried over Na2SO4
4. filtrationfiltered
5. customevaporated to dryness under reduced pressure
6. customThis resulting solid is recrystallised from hot EtOAc/iso-hexane