A new 2-amino imidazole derivative, 5-(4-chlorophenyl)-N,1-di-o-tolyl-1H-imidazole-2-amine (3), has been synthesized using a green approach. The reaction was conducted in a ChCl (cholinium chloride)/urea eutectic mixture, which is a nature-inspired and environmentally friendly reaction medium. The proposed reaction mechanism involves the preliminary regioselective alkylation of the Nsp2 of guanidine (2), followed by an intramolecular condensation between the carbonyl moiety and the secondary N′sp3. Finally, a tautomerization/aromatization step furnished the final product (3). Notably, 2-amino imidazole (3) could be isolated in high yield (91%), just by filtration from the DES/water mixture and subsequent crystallization; the remaining ChCl/urea could be recycled, after water removal, for four consecutive reactions without any significant drop in the (3) yield. The product has been fully characterized by 1H, 13C, 2D 1H-13C HSQC, and 2D 1H-13C HMBC NMR; FT-IR spectroscopy; and EI-MS spectrometry.

中文翻译：

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5-(4-氯苯基)-N,1-二邻甲苯基-1H-咪唑-2-胺

使用绿色方法合成了一种新的 2-氨基咪唑衍生物 5-(4-chlorophenyl)-N,1-di-o-tolyl-1H-imidazole-2-amine (3)。该反应在 ChCl2（氯化胆碱）/尿素低共熔混合物中进行，这是一种受自然启发且环境友好的反应介质。拟议的反应机制涉及胍 (2) 的 Nsp2 的初步区域选择性烷基化，然后是羰基部分和仲 N'sp3 之间的分子内缩合。最后，互变异构化/芳构化步骤提供了最终产物 (3)。值得注意的是，2-氨基咪唑 (3) 可以高产率 (91%) 分离，只需从 DES/水混合物中过滤并随后结晶；剩余的氯仿/尿素经除水后可循环使用，对于四个连续反应，(3) 产率没有任何显着下降。该产品已通过 1H、13C、2D 1H-13C HSQC 和 2D 1H-13C HMBC NMR 进行了全面表征；红外光谱；和 EI-MS 光谱法。