反应详情

2-Amino-5-methyl-3-ethoxycarbonyl-thiophene (5 g) and 4-cyanobenzoic acid methylester (2.7 g) are dissolved in dioxane (40 ml). Gaseous HCl is conducted through the solution for 5 hours. The usual workup yields 4-(3,4-dihydro-4-oxo-6-methyl-thieno-[2,3-d]-pyrimidin-2-yl]-benzoic acid methylester (6 g)