反应详情

温度

-30 °C

To 1-chloro-3,5-dibromobenzene (Esprit) (20 g, 0.074 mole) in anhydrous ethyl ether (150 mL) in a flame dried flask under N2 and at -78° C. was added 1.6 m butyl lithium in hexane dropwise, keeping the temperature below -78° C., then warmed to -30° C. Anhydrous DMF (6.8 g, 0.092 mole) was added dropwise, keeping the temperature below -20° C. After the addition was complete, the reaction was slowly warmed to 0° C., then stirred overnight at room temperature. The reaction mixture was poured slowly into chilled 10% aqueous HCl (160 mL). After stirring for 15 minutes, the ether was separated, washed with H2O (4×), dried over MgSO4 and removed under vacuum to yield 3-bromo-5-chlorobenzaldehyde (13 g) as a white solid. MS and NMR were consistent with the desired structure.

1. customthe temperature below -78° C.
2. customthe temperature below -20° C
3. additionAfter the addition
4. temperaturethe reaction was slowly warmed to 0° C.
5. additionThe reaction mixture was poured slowly
6. stirringAfter stirring for 15 minutes
7. customthe ether was separated
8. washwashed with H2O (4×)
9. dry with materialdried over MgSO4
10. customremoved under vacuum