Reaktion #11247

Reaktionsgleichung

water

diethyl 2-chlorobenzylphosphonate

7-bromo-5-methoxybenzofuran-2-carbaldehyde

sodium hydride

→

( 859 )

Ausbeute 84.0%

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

Ausbeute 84.0%

Lösungsmittel

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was cooled to room temperature
2. 2
   Sonstigethe tetrahydrofuran was removed
3. 3
   workup.ADDITIONWater (50 mL) was added
4. 4
   Extraktionthe mixture was extracted with ethyl acetate (3×100 mL)
5. 5
   WaschenThe combined ethyl acetate extracts were washed with brine (50 mL)
6. 6
   Trocknendried over magnesium sulphate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated to dryness
9. 9
   SonstigeTrituration with diethyl ether (20 mL) gave solid material which
10. 10
    Waschenwas further washed with diethyl ether (20 ml)
11. 11
    EinengenThe liquors were concentrated
12. 12
    Sonstigetriturated with diethyl ether (10 mL)
13. 13
    Sonstigethe solid being collected

Vorschrift

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.

Quelle