New bi-functional zinc catalysts based on robust and easy-to-handle N-chelating ligands for the synthesis of cyclic carbonates from epoxides and CO2 under mild conditions was written by Luo, Rongchang;Zhou, Xiantai;Zhang, Wuying;Liang, Zhongxiu;Jiang, Jun;Ji, Hongbing. And the article was included in Green Chemistry in 2014.Reference of 21252-69-7 This article mentions the following:
Novel zinc complexes were prepared by covalent linkage of various imidazolium-based ionic liquid moieties with the 2,2′-bipyridine ligand on the two sides of the 4,4′-position. The zinc(II) complexes containing the rigid N-chelating ligand proved to be stable, highly efficient and easy-to-handle catalysts towards the synthesis of cyclic carbonate from epoxide and CO2 without the use of any co-catalyst or organic solvent. The catalysts can be easily recovered and reused without significant loss of activity and selectivity by control of the solvent. The kinetic study uncovered that the reaction was 1st-order with respect to the epoxide. Also, a plausible reaction mechanism was proposed, in which the zinc center could promote ring-opening of the epoxide for the synergetic effect with the anion X– in ILs. In the experiment, the researchers used many compounds, for example, 1-Octyl-1H-imidazole (cas: 21252-69-7Reference of 21252-69-7).
1-Octyl-1H-imidazole (cas: 21252-69-7) belongs to imidazole derivatives. The solubility of imidazoles in ethers is lower than that in alcohols and decreases with increasing chain length of the ethers . In contrast, the solubility of benzimidazoles in alcohols (C3–C6) is higher than in water and generally decreases with a Many drugs contain an imidazole ring, such as certain antifungal drugs, the nitroimidazole series of antibiotics, and the sedative midazolam.Reference of 21252-69-7
Referemce:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem