Three Polymeric Frameworks Constructed from Discrete Molybdenum Oxide Anions and 4,4‘-bpy-Bridged Linear Polymeric Copper Cations

• Published in: Chemistry of materials 2002-06, Vol.14 (6), p.2649-2655
• Main Authors: Lu, Can-Zhong, Wu, Chuan-De, Zhuang, Hong-Hui, Huang, Jin-Shun
• Format: Article
• Language: English
• Subjects: Chemistry; Condensed matter: structure, mechanical and thermal properties; Coordination compounds; Exact sciences and technology; Inorganic chemistry and origins of life; Inorganic compounds; Metal complexes; Physics; Preparations and properties; Structure of solids and liquids; crystallography; Structure of specific crystalline solids
• ISSN: 0897-4756; 1520-5002
• DOI: 10.1021/cm011725k

Three compounds, [Cu(4,4‘-bpy)]2MoO4·2H2O (1), [Cu(4,4‘-bpy)]2Mo2O7 (2), and [Cu(4,4‘-bpy)(nic)(H2O)]2Mo8O26 (3), are synthesized by hydrothermal reaction, which suggests that oxomolybdate−organic ligand coordination transition-metal fragments can merge their merit to generate some interesting architectures. Crystal data for [Cu(4,4‘-bpy)]2MoO4·2H2O (1):  monoclinic system, space group C2/c, a = 10.936(1), b = 17.775(1), and c = 14.484(1) Å, β = 110.15(1)°, and Z = 4. Crystal data for [Cu(4,4‘-bpy)]2Mo2O7 (2):  orthorhombic system, space group Pbcn, a = 11.841(1), b = 9.105(1), and c = 21.311(1) Å, and Z = 4. Crystal data for [Cu(4,4‘-bpy)(nic)(H2O)]2Mo8O26 (3):  monoclinic system, space group P2(1)/n, a = 11.457(1), b = 16.918(1), and c = 12.463(1) Å, β = 92.6(1)°, and Z = 2. Compound 1 is built up from {MoO4} tetrahedra linking of 4,4‘-bpy coordination copper(I) chain fragments as a railroad-like framework. Compound 2 has noticeable structural features:  two {Mo2O7} and four {CuO2N2} tetrahedra are connected to each other alternately in a pattern of corner sharing to construct an eight-metal-central-membered cavity; such subunits are connected to each other also through corner-shared, two-dimensional mosaic frameworks, which are linked further by bidentate 4,4‘-bpy ligands to a three-dimensional framework with oval channels. The two-dimensional flat brick wall-like layer structure of 3 is constructed from two layer [Cu(4,4‘-bpy)(nic)(H2O)] n 2 n + chains joined together by β-[Mo8O26]4- units as tethers through covalent bonding of the terminal oxo groups to form rectangular cavities. The most curious feature of 3, however, is that the extended structure of 3 is comprised of an interpenetrated arrangement of two kinds of multizigzag chain polymers entangled together. The successful assembly of the three polymeric frameworks of 1−3 demonstrates the dramatic influence of the reaction acidity/basicity on the organization of molecular building groups and further on the construction of solid architectures. The studies of the temperature dependence of the magnetic susceptibilities of 3 reveal that there exists the weak magnetic transformation of 4,4‘-bpy and octamolybdate between metal ions.