2-Aminothiophene-3-carboxamide → 2-sulfanyl-3H,4H-thieno(2,3-d)pyrimidin-4-one

Participants

Reaction Conditions

Reaction Steps

2-Amino-thiophene-3-carboxlic acid amide (28.4 g, 0.2 mol) and potassium ethylxanthate (96 g, 3 eq) were mixed together and added to DMF (1000 mL). The resulting mixture was heated to 150° C. for about six hours. The solvent (DMF) was removed on the rotovap under high vacuum at 90° C. The residue was diluted with 600 mL of aqueous citric acid (5%) and cooled to 0° C. and stirred for about 30 minutes. The tan powder was filtered and dried overnight to give 25.6 g of the title compound ((M+H)+=185, M.P.>300° C.).

Provenance & Evidence