1260243-04-6

制備方法

94-05-3

1260243-04-6
以乙氧甲叉氰乙酸乙酯為原料合成5-氨基-1H-吡唑-4-羧酸乙酯的一般步驟如下:將乙氧甲叉氰乙酸乙酯(68g,0.4mol)加入裝有200mL無水乙醇的反應(yīng)容器中;緩慢滴加100mL水合肼至反應(yīng)容器中,隨后將反應(yīng)體系置于電熱套中,于30分鐘內(nèi)逐步升溫至80℃,得到混合物A;將混合物A加熱至回流狀態(tài),保持回流反應(yīng)4小時。反應(yīng)完成后,通過減壓蒸餾除去乙醇,剩余固體經(jīng)蒸發(fā)處理。將所得固體冷卻至室溫,靜置析出淺黃色固體,經(jīng)過濾、洗滌及干燥,得到中間體5-氨基-1H-吡唑-4-羧酸乙酯。洗滌過程中使用冷的無水乙醇。最終獲得5-氨基-1H-吡唑-4-羧酸乙酯41.68g,收率為66.78%。
參考文獻(xiàn):
[1] Patent: CN105949202, 2016, A. Location in patent: Paragraph 0048-0053
[2] Patent: CN106008517, 2016, A. Location in patent: Paragraph 0048; 0049; 0050; 0051; 0052; 0053
[3] Patent: CN106008519, 2016, A. Location in patent: Paragraph 0048; 0049; 0050; 0051; 0052; 0053
[4] Patent: CN105949199, 2016, A. Location in patent: Paragraph 0047-0052
[5] Patent: CN105949200, 2016, A. Location in patent: Page/Page column 6; 7; 23