申请人:MITSUI PETROCHEMICAL INDUSTRIES, LTD.
公开号:EP0252162A1
公开(公告)日:1988-01-13
A process for preparing 2-unsubstituted imidazoles which comprises reacting an a-hydroxycarbonyl compound with a formamide in a molar ratio of the formamide to the hydroxycarbonyl compound of 2 or less at a reaction temperature of 100 to 170°C in an atmosphere of ammonia gas. This process makes it possible to obtain 2-unsubstituted imidazoles in an extremely high yield and provides an advantage that recovering procedures involving decomposition of the formamide can be eliminated since it is not used in large excess. Removal of formic acid formed as by-product of the reaction serves to prevent corrosion of reactors and separators such as a distilling tower and yield highly pure imidazoles.
一种制备 2-未取代咪唑的工艺,包括在氨气气氛中,在 100 至 170℃的反应温度下,使 a-羟基羰基化合物与甲酰胺反应,甲酰胺与羟基羰基化合物的摩尔比为 2 或 2 以下。通过这种工艺可以获得产率极高的 2-未取代咪唑,其优点是由于不需要过量使用甲酰胺,因此可以省去涉及甲酰胺分解的回收步骤。除去反应副产物甲酸可防止反应器和分离器(如蒸馏塔)受到腐蚀,并可获得高纯度的咪唑。