Reacción #1994296

Ecuación de reacción

4-chloro-2-fluorobenzaldehyde

sodium hydroxide

acetone

dichloromethane

→

4-(4-chloro-2-fluorophenyl)-3-buten-2-one

Rendimiento 76.0%

(E)-4-(4-chloro-2-fluorophenyl)-but-3-en-2-one

Rendimiento 76.0%

Disolventes

water

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONwas added
2. 2
   OtroThe aqueous layer was separated
3. 3
   Extracciónextracted with CH2Cl2 (100 mL)
4. 4
   Lavadothe combined organic extracts were washed with brine
5. 5
   Secadodried over magnesium sulfate (MgSO4)
6. 6
   OtroSolvent removal
7. 7
   workup.DISTILLATIONfollowed by Kugelrohr distillation

Procedimiento

To a mechanically stirred solution of 4-chloro-2-fluorobenzaldehyde (23.8 grams (g), 0.15 mole (mol)) in acetone (100 milliliters (mL)) at room temperature was added over 20 minutes (min) a solution of sodium hydroxide (NaOH, 6.6 g, 0.165 mol) in water (H2O, 400 mL). After stirring the reaction mixture overnight, dichloromethane (CH2Cl2, 100 mL) was added. The aqueous layer was separated and extracted with CH2Cl2 (100 mL), and the combined organic extracts were washed with brine and dried over magnesium sulfate (MgSO4). Solvent removal followed by Kugelrohr distillation gave 4-(4-chloro-2-fluorophenyl)-3-buten-2-one (1; 22.5 g, 76%) as a colorless liquid, which solidified upon standing: by 70-80° C., 0.1 mmHg (13.33 pascals (Pa)); 1H NMR (400 MHz, CDCl3) δ 7.59 (d, J=16.5 Hz, 1H), 7.50 (t, J=8.1 Hz, 1H), 7.22-7.12 (m, 2H), 6.76 (d, J=16.5 Hz, 1H), 2.39 (s, 3H); HRMS-ESI (m/z): calcd for C10H8ClFO, 198.024. found 198.025.

Fuente