Hydrochloric Acid → 3-butyl-6-ethylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dione

Participants

Reaction Conditions

Reaction Steps

To a mixture of methyl 2-amino-5-ethylthiophene-3-carboxylate (2.5 g), 1-isocyanatobutane (1.52 mL) and tetrahydrofuran (20 ml) was added sodium hydride (1.2 g), and the mixture was stirred at 60° C. for. 5 hr. The reaction mixture was diluted with water, and the mixture was adjusted to pH 4 with 1N hydrochloric acid, the precipitated solid was collected by filtration. The obtained solid was recrystallized from ethyl acetate to give the title compound as colorless crystals (1.85 g, 54%).

Provenance & Evidence