Réaction #2028886

Équation de réaction

4-(2-Thienyl)butyric acid

acetic anhydride

phosphoric acid

→

oil

Rendement 88.9%

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

Rendement 88.9%

Solvants

water

Conditions de réaction

Traitement

1. 1
   Températureheated
2. 2
   Températureto reflux for 3.2 hours
3. 3
   Extractionextracted with ethyl acetate
4. 4
   Lavagewashed with brine
5. 5
   Séchagedried over MgSO4
6. 6
   Concentrationconcentrated in vacuo

Mode opératoire

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.

Source