Syntheses, Structures And Properties Of P-block Metal Complexes With In Situ Synthesized 3,6-dihydroxy-2,5-benzoquinone-1,4-dicarboxylate(diester)

Recently, in situ ligand synthesis under hydro(solvo)thermal conditions has been extensively applied in construction of coordination polymers due to its effectiveness, simplicity and environmental friendliness. In particular, in situ ligand synthesis is often accompanied by some new organic reactions. Thus, the analysis and exploration of reaction mechanism has also been the focus. This dissertation composed of two chapters mainly reports three P-block metal-organic compounds with in stiu synthesized 3,6-dihydroxy-2,5-benzoquinone-1,4-dicarboxylate (diester). Their structures and formation mechanism of the ligand from precursor were discussed in detail.Chapter one is a brief introduction to the hydro(solvo)thermal method, in situ ligand synthesis and research progress of metal benzoquinone complexes. In chapter two, three novel complexes, namely [Bi(dhbqdc)2]·(DMF)n(1), Bi2(dhbqdce)(C2O4)2(DMF)4 (2) and [Bi(dhbqdc)2]·(DMF)n(3) are reported firstly, in which the ligands dhbqdc and dhbqdce are in situ obtained from the precursor dimethyl 1,4-cyclohexanedione-2,5-dicarboxylate. The 1 and 3 show isostructural 3D diamond network, in which eight-coordinated metal ion is chelated by eight hydroxyl groups from four dhbqdc in bis-bidentate fashion. In contrast, the eight-coordinated Bi atom in 2 show a triangular dodecahedron geometry, ligated by two hydroxy groups from one dhbqdce, four carboyxlate oxygen atoms from two oxalates and two carbonyl groups from two DMFs, and the final structure shows a 2D brickwall layer. In addition, the infrared spectrum, X-ray powder diffraction and thermogravimetric analysis are also introduced. Finally, the ligands formation mechanism is discussed, including enol interconversion, oxidation-insert, oxidative aromatization, proton transfer, ester cleavage and so on.