关键词: 水热合成, 混合配体, 多酸配位聚合物, 晶体结构, 催化活性

Abstract: Four POM-based coordination polymers with mixed 4,4’-bipy and 2,2’-bipy/phen, [Cu(4,4’-bipy)(2,2’-bipy)2]2[SiW12O40]?4H2O (1), [Ag4(4,4’-bipy)3(2,2’- bipy)2][SiW12O40]?2H2O (2), [Cu(4,4’-bipy)(phen)]2[H3O]2[SiW12O40]?8H2O (3) and [Cu(4,4’-bipy-Cl)(phen)]2[H3O][PW12O40]?H2O (4) (bipy = bipyridine, phen = phenanthroline), were synthesized under hydrothermal condition and characterized by IR, TG, elemental analysis, and single-crystal X-ray diffraction. Compound 1 is crystallized in the monoclinic system, space group P21/n, with a = 1.2858(4) nm, b = 2.0890(7) nm, c = 1.5580(5) nm, β = 102.306(4)o, V = 4.089(2) nm3, Z = 2, R1 = 0.0451, wR2 = 0.0934. Compound 2 is crystallized in the monoclinic system, space group P21/n, with a = 1.2766(4) nm, b = 2.1258(6) nm, c = 1.4491(4) nm, β = 104.774(4)o, V = 3.803(2) nm3, Z = 2, R1 = 0.0429, wR2 = 0.0730. Compound 3 is crystallized in the monoclinic system, space group C2/m, with a = 1.9850(8) nm, b = 1.4072(6) nm, c = 1.2108(5) nm, β = 110.629(6)o, V = 3.165(2) nm3, Z = 2, R1 = 0.0885, wR2 = 0.1647. Compound 4 is crystallized in the monoclinic system, space group C2/m, with a = 2.0376(7) nm，b = 1.4031(5) nm, c = 1.3784(5) nm, β = 93.502(6)o, V = 3.933(2) nm3, Z = 2, R1 = 0.0561, wR2 = 0.1491. The catalytic activity of these compounds was tested in the epoxidation of styrene and compound 3 and 4 exhibited high conversion of styrene and selectivity to epoxide.

Key words: Hydrothermal synthesis, Mixed ligands, POM-based coordination polymers, Crystal structure, Catalytic activity