Syntheses, Crystal Structures and Properties of Two Metal-organic Complexes Based on 5-(4-Pyridyl)-methoxyl Isophthalic Acid

摘要

Two new metal-organic frameworks, [Co3L2(NO2)2 (H2O)2]n (1) and{[Ni(L)(H2O)5 ]·(H2O)2 ·DMF}n(2, H2 L = 5-(4-pyridyl)-methoxyl isophthalic acid), have been synthesized by the hydrothermal method and characterized by elemental analysis, infrared spectroscopy, thermo-gravimetric analysis (TGA) and X-ray crystallography. Compound 1 crystallizes in the monoclinic system with space group P2/c and adopts a slightly distorted octahedral configuration. In compound 1, the 2D bilayered structures are linked by O-H···O and O-H···N hydrogen bonds to form a 3D framework. Compound 2 crystallizes in the monoclinic system with space group P21 /n, and the central nickel atoms are octa-coordinated with five O atoms from coordinated water molecules and one N atom from one H2L ligand. The abundant O-H···O hydrogen bonds and π···π interactions link the molecules into a 3D framework. In addition, compounds 1 and 2 exhibit strong ultraviolet absorption in the solid state at room temperature.