Reacción #11247

Ecuación de reacción

water

diethyl 2-chlorobenzylphosphonate

7-bromo-5-methoxybenzofuran-2-carbaldehyde

sodium hydride

→

( 859 )

Rendimiento 84.0%

7-Bromo-2-[(E)-2-(2-chlorophenyl)ethenyl]-5-methoxy-1-benzofuran

Rendimiento 84.0%

Disolventes

tetrahydrofuran

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe reaction mixture was cooled to room temperature
2. 2
   Otrothe tetrahydrofuran was removed
3. 3
   workup.ADDITIONWater (50 mL) was added
4. 4
   Extracciónthe mixture was extracted with ethyl acetate (3×100 mL)
5. 5
   LavadoThe combined ethyl acetate extracts were washed with brine (50 mL)
6. 6
   Secadodried over magnesium sulphate
7. 7
   Filtraciónfiltered
8. 8
   Concentraciónconcentrated to dryness
9. 9
   OtroTrituration with diethyl ether (20 mL) gave solid material which
10. 10
    Lavadowas further washed with diethyl ether (20 ml)
11. 11
    ConcentraciónThe liquors were concentrated
12. 12
    Otrotriturated with diethyl ether (10 mL)
13. 13
    Otrothe solid being collected

Procedimiento

To a solution of diethyl 2-chlorobenzylphosphonate (4.91 g, 0.018 mol) and 7-bromo-5-methoxybenzofuran-2-carbaldehyde (11.27 g, 0.016 mol) in tetrahydrofuran (80 mL) was added sodium hydride (60% dispersion in mineral oil, 0.74 g, 0.0185 mol). After 5 min. the reaction mixture was warmed to 60° C. for 1 h. The reaction mixture was cooled to room temperature, water (10 mL) was carefully added and the tetrahydrofuran was removed. Water (50 mL) was added and the mixture was extracted with ethyl acetate (3×100 mL). The combined ethyl acetate extracts were washed with brine (50 mL), dried over magnesium sulphate, filtered and concentrated to dryness. Trituration with diethyl ether (20 mL) gave solid material which was further washed with diethyl ether (20 ml). The liquors were concentrated and triturated with diethyl ether (10 mL), the solid being collected. The combined solids gave (859) (4.89 g, 84%). 1H NMR δ (CDCl3) 7.70 (d, J=16 Hz, 1H), 7.65 (dd, J=7.7, 1.5 Hz, 1H), 7.4 (dd, J=6.0, 1 Hz, 1H), 7.23 (m, 2H), 7.05 (d, J=2.3 Hz, 1H), 6.94 (d, J=16 Hz, 1H), 6.92 (d, J=2.3 Hz, 1H), 6.72 (s, 1H), 3.82 (s, 3H); MH+:364.9, 362.9 MH−:362.9, 360.9.

Fuente