Metal-directed assembly of organic–inorganic complexes constructed from V-shaped linkages

Three new complexes based on V-shaped linkages 2,5-bis(4-pyridyl)-1,3,4-thiadiazole (bpt) and 4,4′-oxybis(benzoic acid) (H2oba), [Mn(bpt)(oba)(H2O)3]n·nH2O (1), [Co2(bpt)2(oba)(H2O)7]·(oba) (2), and [Cd2(oba)2(H2O)6]n·2n(bpt)·2nH2O (3) have been synthesized using different transition metal acetates. Non-covalent hydrogen bonding interactions extend complexes 1, 2 and 3 into supramolecular architectures. Complex 1 is a 3D framework, in which two types of helical H-bonded chains appear simultaneously. Complexes 2 and 3 contain 1D open channels encapsulating organic guest molecules – oba and bpt, respectively. Topologically, complex 3 is a α-Po structure. This work indicates that the building blocks oba and bpt can adopt versatile coordination modes depending on the nature of the metal centers. The elemental analysis, IR spectra, XRPD and TG analysis for three complexes, as well as luminescent properties for 3 are discussed.