Reaktion #2028886

Reaktionsgleichung

4-(2-Thienyl)butyric acid

acetic anhydride

phosphoric acid

→

oil

Ausbeute 88.9%

4-keto-4,5,6,7-tetrahydrothianaphthene

Ausbeute 88.9%

Lösungsmittel

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated
2. 2
   Temperaturto reflux for 3.2 hours
3. 3
   Extraktionextracted with ethyl acetate
4. 4
   Waschenwashed with brine
5. 5
   Trocknendried over MgSO4
6. 6
   Einengenconcentrated in vacuo

Vorschrift

4-(2-Thienyl)butyric acid (28.42 g, 167 mmol) was placed in a round bottom flask with acetic anhydride (30 mL) and phosphoric acid (0.6 mL), and heated to reflux for 3.2 hours. The reaction mixture was poured into 100 mL of water, extracted with ethyl acetate, washed with brine, dried over MgSO4, and concentrated in vacuo to give a brown oil (22.60 g) which was vacuum distilled (1 mm Hg, 107°-115° C.) to give a white solid (13.08 g, 51%): mp 34°-40° C.); 1H NMR (CDCl3) 300 MHz 7.29 (d, J=5.2 Hz, 1H), 6.99 (d, J=5.2 Hz, 1H, 2.95 (t, J=6.0 Hz, 2H), 2.47(m, 2H), 2.13(m, 2H). M+H=153.

Quelle