反应详情

In 14 ml. of isopropyl alcohol were dissolved 1.4 g. of methyl 6-chloro-5-ethylamino-3-methoxypyrazine-2-carboxylate and 1.4 g. of N,N-diethylethylenediamine and the solution was refluxed for 4 days. After the reaction was over, the solvent was distilled off under reduced pressure from the reaction mixture and the residue obtained was applied to a silica gel column chromatography. The column was then developed using a mixture of ether and N-hexane of 1:1 volume ratio as an eluting solution. From the 1st fraction 0.7 g. of methyl 5-ethylamino-6-chloro-3-methoxypyrazine-2-carboxylate used as the starting material was recovered and from the 2nd fraction 0.7 g. of colorless plate crystals of N-(2-diethylaminoethyl)-6-chloro-5-ethylamino-3-methoxypyrazine-2-carboxamide a melting at 142° C. were obtained. The product obtained by recrystallizing the crystals from a mixture of benzene and n-hexane melted at 142° C.

1. distillationwas distilled off under reduced pressure from the reaction mixture
2. customthe residue obtained
3. customwas recovered and from the 2nd fraction 0.7 g