Reaktion #1088

Reaktionsgleichung

3-bromo-benzo[b]thiophene

4-benzyloxyphenol

→

benzo[b]thiophene

Ausbeute 28.0%

Lösungsmittel

collidine

ethyl acetate

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was heated
2. 2
   Temperaturto reflux for 24 hours
3. 3
   TemperaturUpon cooling
4. 4
   Filtrationthe crude mixture filtered through a pad of Celite® (Aldrich, Milwaukee, Wis.)
5. 5
   Sonstigeto remove inorganic salts
6. 6
   WaschenThe filtrate was washed with 1N hydrochloric acid (3×150 mL)
7. 7
   TrocknenThe organic was dried (sodium sulfate)
8. 8
   Einengenconcentrated in vacuo to a liquid
9. 9
   SonstigeThianaphthene was removed by distillation (10 mm Hg, 115°-120° C.)
10. 10
    SonstigeThe remainder of the material was chromatographed (silicon dioxide, hexanes: ethyl acetate 85:15)

Vorschrift

To a solution of 3-bromo-benzo[b]thiophene (69.62 g, 0.325 mol) in 55 mL of anhydrous collidine under N2 was added 4-benzyloxyphenol (97.6 g, 0.488 mol) and cuprous oxide (23.3 g, 0.163 mol). The mixture was heated to reflux for 24 hours. Upon cooling, the reaction mixture was diluted with ethyl acetate (200 mL) and the crude mixture filtered through a pad of Celite® (Aldrich, Milwaukee, Wis.) to remove inorganic salts. The filtrate was washed with 1N hydrochloric acid (3×150 mL). The organic was dried (sodium sulfate) and concentrated in vacuo to a liquid. Thianaphthene was removed by distillation (10 mm Hg, 115°-120° C.). The remainder of the material was chromatographed (silicon dioxide, hexanes: ethyl acetate 85:15) to provide 12.2 g of benzo[b]thiophene and 12.95 g (35% based on recovered starting material) of [3-(4-benzyloxy)phenoxy]benzo-[b]thiophene as an off-white solid. mp 84°-86° C. 1H NMR (CDCl3) d 7.91-7.83 (m, 2H), 7.47-7.34 (m, 7H), 7.04 (q, JAB =9.0 Hz, 4H), 6.47 (s, 1H), 5.07 (s, 2H). Anal. Calcd. for C21H16O2S: C, 75.88; H, 4.85. Found: C, 75.75; H, 5.00.

Quelle