Reacción #79339

Ecuación de reacción

2-Bromo-5-fluoro-N-methoxy-N-methylbenzamide

Methyl magnesium bromide

→

1-(2-bromo-5-fluorophenyl)ethanone

Rendimiento 93.0%

Disolventes

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe solution was warmed to room temperature
2. 2
   TemperaturaThe solution was cooled to 0° C.
3. 3
   Otroquenched with HCl/EtOH (9 mL, 4 M solution)
4. 4
   OtroThe reaction mixture was transferred to a separatory funnel
5. 5
   workup.ADDITIONdiluted with H2O (30 mL)
6. 6
   Extracciónextracted with Ethyl Acetate (2×40 mL)
7. 7
   LavadoThe combined organic extracts were washed with H2O, brine
8. 8
   Secadodried over Na2SO4
9. 9
   ConcentraciónThe solution was concentrated

Procedimiento

2-Bromo-5-fluoro-N-methoxy-N-methylbenzamide (4.0 g, 0.015 mol) was dissolved in THF (30 mL) and the solution was cooled to 0° C. under N2blanket. Methyl magnesium bromide (15.26 mL, 0.046 mol) was added dropwise over 30 min. The solution was warmed to room temperature and stirred for 1 hour. The solution was cooled to 0° C. and quenched with HCl/EtOH (9 mL, 4 M solution). The reaction mixture was transferred to a separatory funnel, diluted with H2O (30 mL), and extracted with Ethyl Acetate (2×40 mL). The combined organic extracts were washed with H2O, brine, and dried over Na2SO4. The solution was concentrated to afford 1-(2-bromo-5-fluorophenyl)ethanone as a yellow oil in 93% yield . This material was used in the subsequent step without further purification. 1H NMR (CDCl3, 500 MHz) δ2.61 (s, 3H), 7.00-7.04 (m, 1H) 7.15-7.18 (m, 1H), 7.53-7.59 (m, 1H).

Fuente