反应详情

温度

-30 °C

An oven dried 500 mL flask, was charged under nitrogen with (S)-2-methyl-CBS-oxazaborolidine 1M in toluene (5.02 mL) and dissolved in CH2Cl2 (250 mL). Me2-BH3 (30 mL, 60.27 mmol) was then added and cooled to −30° C. and reaction stirred for 15 minutes. (1-(4-Bromo-2-fluoro-phenyl)-ethanone (10.9 g, 50.23 mmol) from step 2 below was dissolved in CH2Cl2 (10 mL) and slowly added via addition funnel to the previous solution. The resulting reaction was stirred at 25° C. overnight. The solution was carefully quenched with MeOH, the solvent was removed in vacuo and the residue was purified by flash column chromatography (20% EtOAc in hexanes) to provide the desired product (9 37 g, 90%) as a clear oil. 1H NMR (400 MHz, CDCl3): δ 1.49 (d, J=6.6 Hz, 3H), 5.15 (q, J=12, 6.4 Hz, 1H), 7.15–7.45 (m, 3H).

1. customAn oven dried 500 mL flask
2. additionwas charged under nitrogen with (S)-2-methyl-CBS-oxazaborolidine 1M in toluene (5.02 mL)
3. dissolutiondissolved in CH2Cl2 (250 mL)
4. additionMe2-BH3 (30 mL, 60.27 mmol) was then added
5. customreaction
6. additionslowly added via addition funnel to the previous solution
7. customThe resulting reaction
8. stirringwas stirred at 25° C. overnight
9. customThe solution was carefully quenched with MeOH
10. customthe solvent was removed in vacuo
11. customthe residue was purified by flash column chromatography (20% EtOAc in hexanes)