反应详情

温度

-75 °C

Sodium hydride (60% in mineral oil, 1.23 g) was added in portions to a solution of N-ethyl-3-fluoro-5-iodo-4-methylbenzamide (Intermediate 4, 4.81 g) in anhydrous THF (75 ml). The resulting mixture was cooled to −75° C. and n-butyllithium (1.6M in hexanes, 20 ml) was added dropwise over 20 min. Triisopropylborate (8 ml) was added over 5 min and the reaction mixture was stirred at −75° C. for 6 h. Water (20 ml) was added and the mixture was warmed to 15° C. overnight and the mixture was partitioned between saturated aqueous ammonium chloride and ethyl acetate. The organic phase was washed with aqueous ammonium chloride and brine, dried (MgSO4) and concentrated under vacuum. The residue was dissolved in dichloromethane and applied to a silica column (10 g) eluting with an ethyl acetate/dichloromethane gradient (0-100% ethyl acetate) followed by methanol. The methanol fractions were concentrated under vacuum to give the title compound as an off-white foam (550 mg).

1. temperaturethe mixture was warmed to 15° C. overnight
2. customthe mixture was partitioned between saturated aqueous ammonium chloride and ethyl acetate
3. washThe organic phase was washed with aqueous ammonium chloride and brine
4. dry with materialdried (MgSO4)
5. concentrationconcentrated under vacuum
6. dissolutionThe residue was dissolved in dichloromethane
7. washeluting with an ethyl acetate/dichloromethane gradient (0-100% ethyl acetate)
8. concentrationThe methanol fractions were concentrated under vacuum