Substituted guanidines were synthesized by the guanylation of amines with carbodiimides using Zn–Al hydrotalcite (Zn-Al HT) catalyst. Zn–Al HT was prepared by co-precipitation method and characterized by X-ray powder diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Raman and Thermogravimetric-Differential Thermal Analysis (TG-DTA). The heterogeneous catalyst afforded moderate to good yields (∼50–60 %) of substituted guanidines in toluene at 110°C in 12 h. The catalyst was recovered quantitatively by simple filtration and reused for three cycles with consistent activity. The XRD and FTIR studies of the used catalyst shows no variation in the structure of the catalyst even after three recycles.
使用
锌铝氢铝酸盐(Zn-Al HT)催化剂通过
氨基与碳化二
亚胺的
鸟苷酸化反应合成了取代的
胍类化合物。Zn-Al HT 采用共沉淀法制备,并通过 X 射线粉末衍射 (XRD)、傅立叶变换红外光谱 (FTIR)、拉曼和热重-差热分析 (TG-DTA) 进行表征。该异相催化剂在 110°C 的
甲苯中,12 h 内可生成中等至良好产率(50-60 %)的取代
胍类化合物。催化剂通过简单过滤即可定量回收,并重复使用了三个周期,活性始终如一。对使用过的催化剂进行的 XRD 和 FTIR 研究表明,即使经过三次循环,催化剂的结构也没有发生变化。