Acetone → HCID 19788972, compound

Participants

Reaction Steps

Bithienylcarboxylic acid in a quantity of 12.3 g is refluxed with 25 ml thionylchloride for 30 min. After evaporating in vacuo the residual carbonylchloride is obtained in a yield of 13.7 g; m.p. 74° C. The carbonylchloride is converted to the corresponding azide by adding a solution of 1.6 g sodium azide in 5 ml water to a solution of said carbonylchloride in 25 ml of acetone. After 30 min at 0° C., ice water is added and the solid is sucked off. After drying 5-azido-carbonyl-2,2'-bithiophene is obtained in a yield of 4.6 g; m.p. 76° C. A mixture of the azidocompound (4.6 g) and 50 ml of abs. ethanol is refluxed for approximately 8 h. After decoloration with charcoal, the filtrate is evaporated and the residue is crystallized from petroleum ether. The desired 5-ethoxycarbonylamino-2,2'-bithiophene is obtained in a yield of 2.4 g; m.p. 98° C. Elementary analysis: 52.45% C (calc. 52.15), 4.36% H (calc. 4.38), 5.63% N (calc. 5.53) and 25.73% S (calc. 25.32).

Provenance & Evidence