Two Novel Titanium(IV)-Based Compounds Supported by Thiacalix[4]arene: Syntheses, Structures and Photocatalytic Properties

Two novel compounds, named [Ti2Na4(BTC4A)(2)(mu(6)-O2-)(CH3O-)(2)center dot 2H(2)O center dot 2DMA] (1) and [Ti-4(BTC4A)(OH-)(4)(EtO-)(6)((PrO-)-Pr-i)(2)] (2) (H(4)BTC4A= p-tert-Butylthiacalix [4] arene), have been synthesized and characterized. Single crystal diffraction shows that compound1features a dumbbell-like molecule based on an octahedral Ti(2)Na(4)core and two BTC4A(4-)ligands with cone conformation. Compound2is composed of a bi-titanium(IV) unit and a BTC4A(4-)ligand with 1,2-alternate conformation. The estimated optical bandgaps of compounds1and2are 2.87 and 1.97 eV, respectively, which are smaller than that of TiO2. Moreover, compounds1and2display much higher and more efficient photocatalytic degradation abilities for methylene blue than TiO(2)under visible light irradiation.