反应详情

Boron tribromide (1.0 M solution in dichloromethane, 110 ml, 0.11 mol) was added dropwise to a stirred solution of N-(4-chloro-3-methylisothiazol-5-yl)-2-(4-methoxyphenyl)propionamide (125 g, 0.040 mol) in dichloromethane (200 ml) at −70° C. Once the addition was complete the cooling bath was removed and the mixture was allowed to warm to room temperature overnight. The mixture was cooled to 0° C. and excess methanol added cautiously. The solvent was evaporated in vacuo, and the residue was partitioned between ethyl acetate and brine. The organic layer was dried over anhydrous magnesium sulfate, filtered and the filtrate was evaporated in vacuo to give N-(4-chloro-3-methylisothiazol-5-yl)-2-(4-hydroxyphenyl)propionamide (11.8 g), which was used without further purification in the next step.

1. additionOnce the addition
2. customwas removed
3. temperatureThe mixture was cooled to 0° C.
4. additionexcess methanol added cautiously
5. customThe solvent was evaporated in vacuo
6. customthe residue was partitioned between ethyl acetate and brine
7. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
8. filtrationfiltered
9. customthe filtrate was evaporated in vacuo