反应详情

The title compound was prepared by (a) reaction of diethylethoxymethylenemalonate (6 g, 28 mmol) with acetamidine hydrochloride (3 g, 31 mmol) to afford 67% of ethyl 2-methyl-4-hydroxypyrimidine-5-carboxylate in analogy to Example 15, (b) reaction of ethyl 2-methyl-4-hydroxypyrimidine-5-carboxylate (2.8 g, 15 mmol) with POCl3 (46 g, 300 mmol) to afford 28% of ethyl 4-chloro-2-methylpyrimidine-5-carboxylate, (c) reaction of ethyl 4-chloro-2-methylpyrimidine-5-carboxylate (0.25 g, 1.25 mmol) with hydrazine (0.2 g, 6.3 mmol) to afford 96% of 4-hydrazino-2-methylpyrimidine-5-carboxylate in analogy to Example 18, (d) reaction of 4-hydrazino-2-methylpyrimidine-5-carboxylate (0.24 g, 1.2 mmol) with citraconic anhydride (0.16 g, 1.44 mmol) to afford 70% (0.24 g) of the title compound (m.p. 98-99° C.) in analogy to Example 21.