Synthesis and Crystal Structure of a New Complex Constructed from a Flexible Tetrapyridyl Ligand

The title complex Cd2(NO3)2(OCH3)2(TPOM)2]·8H2O (TPOM = tetrakis(4-pyri- dyloxymethylene) methane) has been synthesized and characterized by IR spectroscopy, elemental analysis and single-crystal X-ray diffraction. It crystallizes in the orthorhombic crystal system Ccca with a = 17.125(2), b = 40.751(3), c = 24.938(2) ?, β = 90.00o, V = 17403(3) ·3, C26H27N5O8Cd, Mr = 649.93, Z = 16, F(000) = 5280, Dc = 0.992 mg/m3, μ(MoKα) = 0.538 mm-1, S = 1.080, the final R = 0.0533 and wR = 0.1449 for 6627 observed reflections (I > 2σ(I)). The crystal structure shows that each Cd atom is coordinated to four pyridyl nitrogen atoms from four TPOM ligands and each tetrahedral TPOM ligand links up four Cd atoms into a 2-fold interpenetrating 3D framework. The TG analysis shows that the framework of the title complex is stable up to 300 ℃.