Synthesis method of cyanoacetamide

The embodiment of the invention provides a cyanoacetamide synthesis method, which comprises the following steps: slowly adding liquid ammonia into a methyl cyanoacetate solution in a reaction environment of -10 DEG C to-5 DEG C; and after the reaction is completed, controlling the reaction environment to be within the range of -15 DEG C to-10 DEG C, and separating out cyanoacetamide crude crystals. Methyl cyanoacetate directly reacts with liquid ammonia, the liquid ammonia gasification step is reduced, and the reaction temperature is reduced. The reaction process is simple, and high reaction yield can be stably obtained. 本发明实施例提供了一种氰乙酰胺的合成方法，所述方法包括：在-10℃～-5℃的反应环境下，向氰乙酸甲酯溶液中，缓慢加入液氨；在反应完成后，控制所述反应环境处于-15℃～-10℃的范围内，析出氰乙酰胺粗品结晶。氰乙酸甲酯直接与液氨进行反应，减少液氨气化环节，降低了反应温度。反应过程简单，可以稳定获得较高的反应收率。