The Synthesis And Properties Of Coordination Compounds Based On The Derivatives Of Mercapto Tetrazole Ligand

Mercapto tetrazole and its derivatives is a kind of heterocyclic thiol ligands with two kinds of coordinating atoms: N and S atoms which have thiol-thione tautomerism. The derivatives of mercapto tetrazole have attracted the research interests due to their diverstified coordination modes. In this paper, eight coordination compounds and three derived framework compounds based on 1-methyl-5- mercapto tetrazole(HMMTZ) or 1-phenyl-5-mercapto tetrazole(HPMTZ) have been synthesized at room temperature or under solvothermal conditions and characterized by Infrared spectra(IR), thermogravimetric analysis(TGA), and single-crystal X-ray diffraction etc. Moreover, magnetic and luminescent properties of the complexes have also been studied. The main contents as follows:1. Four compounds based on HMMTZ ligand have been successfully synthesized at room temperature or under solvothermal conditions, namely: [(Zn4O)(MMTZ)6]·Et OH(1), [Zn(4,4′-bipy)(MMTZ)2]n(2), [Zn(MMTZ)2]n(3), [Cu4Br(CN)(MTZ)2]n(MTZ = 5-methyl tetrazole)(4). Compounds 1-3 were synthesized at room temperature. Compound 1 is a 0D mononuclear structure, which were further stacked to form a 3D framework. Compound 2 is 1D z igzag chain structure, in which 4,4′-bipy acts as an effectively organic linker. 3 also adopted a one-dimensional chain structure, however, in which MMTZ acts as an organic linker, different from compound 2. The difference of synthesis conditions between 1 and 3 is the different solvent, as revealed that the solvents play an important role in the synthsis of the targeted compounds. Compound 4 is a novel Cu(I) coordination polymer with Cu6Br2 and Cu2(CN)2 SBUs which was synthesized through several in situ reactions including the reduction of Cu(II), a ring-to-ring conversion of the organic heterocycle and the formation of cyanide. The solid-state luminescent properties of compound 1, 2 and 4 were investigated. We can see green fluorescence of 4 directly under ultraviolet light. The fluorescence properties of compound 4 were investigated in various solvent emulsions, the results show that compound 4 is a highly sensitive naked-eye colorimetric sensor for NB and 2-NT. We prepared a fluorescence membrane of compound 4 on glass substrates to detect NB and 2-NT. When theNB/2-NT was dropped on the fluorescence membrane, the bright green fluorescence was changed to the dark state of the film under UV light.2. Four complexes have been obtained based on HPMTZ at room temperature or under solvothermal conditions, namely, [Cd(PMTZ)2]n(5), [Co(PMTZ)2]n(6), [Co2(OH)2(2,2′-bipy)2(HPMTZ)2](PMTZ)2·(CH3OH)2(7), [Cd2I2(2,2′-bipy)2(PMTZ)2](8). Single-crystal X-ray diffraction analyses revealed that isomorphic compounds 5 and 6 both possesses an 1D chain structure, in which PMTZ adopts μ2 coordination modes, and the 1D chains were further stacked to form a 2D layer. In 7, HPMTZ adopting μ2-(κN4: κS) coordination mode and μ2-OH joined two Co centers into a binuclear cobalt structure with short Co?Co distance(2.8185?), however, the deprotoned PMTZ- anions act as counter ion. In compound 8, PMTZ- adopted μ2-(κ2S) coordination mode to link two Cd centers into a binuclear structure. The emissions of compound 5, 8 are tentatively attributed to the internal electronic transition of HPMTZ. Variable-temperature magnetic susceptibility measurement of 6 indicate strong antiferromagnetic interactions between the cobalt centers.3. Three compounds have been synthesized under solvothermal conditions or at room temperature via the in situ reaction of organic Sulphur ligands, namely, [Cu3(SO4)(OH)4]n(9), [Cu3(SO4)2(OH)2]n(10), [(C7H5N4S)2]n(11). Compounds 9 and 10 were synthesized under solvothermal conditions, interestingly, the SO42-ion derived from desulfurized reaction of the HMMTZ. There is an inorganic framework constructed by Cu2+ and SO42- in 9 which has two kinds of channels(I: 4.60×4.94 ?2、II: 7.55×9.63?2). And Channel II was occupied by [Cu(OH)4] unit. In 10, Cu2+ and SO42- are also formed an inorganic framework that has two kinds of channels(I: 3.91×4.60 ?2、II: 7.57×9.64?2). But the difference is Channel II in 10 was occupied by [Cu(OH)2] unit. Compound 11 is an organic compound, which was obtained by in situ coupled reaction of HPMTZ at room temperature. 11 is a 3D supramolecular structure constructed by molecular(C7H5N4S)2 via hydrogen bonding s and π-π stacking interactions.