Reacción #5452

Ecuación de reacción

6-bromo-5-chlorovanillin

1.8-diazabicyclo[5,4,0]-7-undecene

methyl iodide

diisopropylethylamine

methyl iodide

→

title compound

Rendimiento 71.0%

2-Bromo-3-chloro-4,5-dimethoxybenzaldehyde

Rendimiento 71.0%

Disolventes

acetonitrile

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaunder cooling with ice
2. 2
   Temperaturaunder cooling with ice
3. 3
   workup.STIRRINGthe mixture was stirred for 20 hours at room temperature
4. 4
   workup.DISTILLATIONAfter distilled off the solvent, 200 ml of dichloromethane
5. 5
   workup.ADDITIONwere added to the residue, which
6. 6
   Lavadowas washed with water
7. 7
   SecadoAfter dried over anhydrous magnesium sulfate
8. 8
   Otrothe concentrated residue was purified by means of silica gel column chromatography (hexane-AcOEt 5:1)

Procedimiento

Into 50 ml of acetonitrile were suspended 5.39 g (20.3 mmol), of 6-bromo-5-chlorovanillin, and 3.04 ml (20.3 mmol) of 1.8-diazabicyclo[5,4,0]-7-undecene and 2.53 ml (40.6 mmol) of methyl iodide were added dropwise under cooling with ice. After stirred for 5 hours at room temperature, 3.9 ml (22.33 mmol) if diisopropylethylamine and 2.53 ml (40.6 mmol) of methyl iodide were added under cooling with ice and the mixture was stirred for 20 hours at room temperature. After distilled off the solvent, 200 ml of dichloromethane were added to the residue, which was washed with water. After dried over anhydrous magnesium sulfate, the concentrated residue was purified by means of silica gel column chromatography (hexane-AcOEt 5:1) to obtain 4.04 g (yield 71%) of title compound as colorless needle-like crystals.

Fuente