Construction and isomer recognition of polyoxometalates functionalized by 1,2-dimethylimidazole alkane templates

•Eleven polyoxometallates were synthesized by the cation-templated self-assembly.•These compounds were all composed of methylimidazolium cations and polyacid anions.•The anion fraction could take on α-, β-, γ-[Mo8O26]4− or [Mo6O19]2− anion cluster.•In complexes 10 and 11 there coexist two kinds of polyoxomolybdate anions.

Eleven novel inorganic–organic hybrid polyoxometallates, namely, [1,2-bis(1,2-dimethylimidazole)methane]3[β-HMo8O26]2·[H3O+]2·7H2O (1), [1,2-bis(1,2-dimethylimidazole)ethane]2[β-Mo8O26]·H2O (2), [1,2-bis(1,2-dimethylimidazole)propane]2[α-Mo8O26] (3), [1,2-bis(1,2-dimethylimidazole)butane]2[γ-Mo8O26] (4), [1, 2-bis(1,2-dimethylimidazole) pentane]3[β-Mo8O26]2[H3O+]2 (5), [1,2-bis(1,2-dimethylimidazole) hexane]4[β-Mo8O26]2 (6), [1,2-bis(1,2-dimethylimidazole)heptane][Mo6O19] (7), [1,2-bis(1,2-dimethylimidazole) octane] [Mo6O19] (8), [1,3,5-tris[(1,2-dimethylimidazole-3-iumyl)benzene)]2[β-Mo8O26]1.5·2H2O (9), [1,3,5-tris[(1,2-dimethylimidazole-3-iumyl)-2,4,6-trimethyl benzene)]4 [α-Mo8O26]2 [Mo6O19]2·4H2O (10), [1,3,5-tris[imidazol-1-ylmethyl)-2,4,6-trimethyl benzene)]2 [β-Mo8O26] [Mo6O19] (11) were synthesized by the cation-templated self-assembly with octamolybdate or hexamolybdate anions under hydrothermal reaction conditions. Crystal data analysis revealed that these compounds were all composed of discrete organic cations and polyacid anions interacted by electrostatic and hydrogen bond interactions. Interestingly in these compounds the anion fraction could take on [β-Mo8O26]4− cluster, α-[Mo8O26]4− cluster, γ-[Mo8O26]4− cluster, [Mo6O19]2− cluster or two mixing kinds of polyoxomolybdate anions with the modification of lengths of alkane components or change the valence configuration of the templates.

Graphical abstractEleven novel inorganic–organic hybrid polyoxometalates were synthesized by the cation-templated self-assembly with octamolybdate or hexamolybdate anions under hydrothermal reaction conditions.Figure optionsDownload full-size imageDownload as PowerPoint slide