Reacción #81739

Ecuación de reacción

triethylamine

4-bromobenzenesulphonyl iodide

tert-butyl 2-(2-methoxyethoxymethyl)acrylate

→

oil

Rendimiento 96.3%

(E)-tert-Butyl 2-(2-methoxyethoxymethyl)-3-(4-bromobenzenesulphonyl)acrylate

Rendimiento 96.3%

Disolventes

water

dichloromethane

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturacooled to 0° C.
2. 2
   workup.STIRRINGThe reaction was stirred at 0° C. for 0.5 hours and at room temperature for 1.0 hour
3. 3
   Otrothe layers separated
4. 4
   ExtracciónThe aqueous layer was further extracted with dichloromethane (2×5 mL)
5. 5
   Lavadothe combined organic extracts were washed with 1.0M aqueous hydrochloric acid solution (20 mL), 5% aqueous sodium thiosulphate solution (20 mL)
6. 6
   workup.DISTILLATIONdistilled water (20 mL)
7. 7
   SecadoThe dichloromethane phase was dried (MgSO4)
8. 8
   Filtraciónfiltered
9. 9
   Concentraciónconcentrated under reduced pressure

Procedimiento

To a solution of 4-bromobenzenesulphonyl iodide (1.06 g, 3.15 mmol) in dichloromethane (4.5 mL) at room temperature was added tert-butyl 2-(2-methoxyethoxymethyl)acrylate (0.45 g, 2.1 mmol). The mixture was stirred at room temperature for 2.5 hours, cooled to 0° C. and triethylamine (0.58 mL, 4.2 mmol) added dropwise. The reaction was stirred at 0° C. for 0.5 hours and at room temperature for 1.0 hour, diluted with distilled water (20 mL) and dichloromethane (15 mL) and the layers separated. The aqueous layer was further extracted with dichloromethane (2×5 mL) and the combined organic extracts were washed with 1.0M aqueous hydrochloric acid solution (20 mL), 5% aqueous sodium thiosulphate solution (20 mL) and distilled water (20 mL). The dichloromethane phase was dried (MgSO4), filtered and concentrated under reduced pressure to give a brown oil (0.88 g). The crude product was purified by chromatography on silica by gradient elution with hexane/ethyl acetate mixtures to give, after combination and evaporation of appropriate fractions, the title compound as a yellow oil (0.75 g, 83%), Rf =0.39 (silica; hexane/ethyl acetate, 2:1).

Fuente