Reacción #2856

Ecuación de reacción

3-thiophene-2-yl-acrylic acid

triethylamine

tributylamine

sodium azide

ethyl chloroformate

→

title compound

Rendimiento 49.7%

5H-Thieno[3,2-c]pyridin-4-one

Rendimiento 49.7%

Disolventes

acetone

diphenyl ether

H2O

—

hexanes

H2O

Condiciones de reacción

Tratamiento posterior

1. 1
   FiltraciónA white precipitate forms which is collected by filtration
2. 2
   SecadoThe resulting solid is dried over P2O5 under vacuum
3. 3
   workup.WAITAfter 2 h
4. 4
   Temperaturathe solution is cooled to ambient temperatures
5. 5
   Temperaturais cooled to 0° C
6. 6
   FiltraciónThe resulting solid is collected by filtration
7. 7
   Lavadothe solid is washed with hexanes

Procedimiento

To a solution of 3-thiophene-2-yl-acrylic acid (7.39 g, 47.9 mmol) in 200 mL of acetone is added triethylamine (4.9 g, 47.9 mmol). The resulting solution is cooled to 0° C. and ethyl chloroformate (5.7 g, 52.8 mmol) is added dropwise. After 2 h, sodium azide (4.67 g, 71.9 mmol) in 25 mL of H2O is then added. The solution is stirred for 1.5 h at 0° C. After this time, the solution is poured into 300 mL of H2O. A white precipitate forms which is collected by filtration. The resulting solid is dried over P2O5 under vacuum. The solid is suspended in 20 mL of diphenyl ether. This solution is added dropwise to a solution of tributylamine (6.9 g, 37.4 mmol) in 200 ml of diphenyl ether at 190° C. After 2 h, the solution is cooled to ambient temperatures. The solution is diluted with 1000 mL of hexanes and is cooled to 0° C. The resulting solid is collected by filtration and the solid is washed with hexanes. The title compound (3.6 g, 23.8 mmol) is obtained as a white solid.

Fuente