| In the realm of supramolecular chemistry and crystal engineering, great interest has recently been focused on the design and synthesis of complicated multidentate ligands with the purpose of creating novel complexes, which may be applicated in nonlinear optics, molecular selection, ion exchange, catalysis and magnetic materials. As a typical systerm of enol-keto tautomerism,β-diketone ligands and their derivatives have played a significant role in coordination chemistry for over a century. In this paper, the study forβ-diketonate complexes has been reviewed. Sixβ-diketone derivatives and twelve transition metal complexes withβ-diketone ligands were synthesized.This thesis consists of the following two parts:Part 1: Sixβ-diketone derivatives: 2,6-bis(3-oxo-3-phenylpropionyl)-pyridine N-oxide (H2L1), 2-(3-oxo-3-phenylpropionyl)-6-pyridinecarboxylic acid N-oxide (H2L2), 2-(3-oxo-3-(3'-naphthyl)-propionyl)-6-pyridinecarboxylic acid N-oxide (H2L3), 2,6-bis(3-oxo-3-phenylpropionyl)-pyridine (H2L4), 2-(3-oxo-3-phenylpropionyl)-6-pyridinecarboxylic acid (H2L5) and 1,4-bis(3'-methyl-1'-phenyl-5'-pyrazolone-4'-yl) benzenedione (H2L6), which are characterized as symmetric and asymmetricβ-diketonate groups respectively, were designed and synthesized. All compounds were characterized by elemental analyses, UV-Vis, IR, 1H NMR, fluorescence spectra and the crystal structures of H2L2, H2L4, H2L5 and H2L6 were determined by single crystal X-ray diffraction methods. At room temperature, upon excitation at 340 nm, H2L4 performs stronger emission at 461nm. By contrast with its solution fluorescence, the emission peak position of H2L4 is obvious blue shift.Part 2: Twelve novel transition-metal complexes have been synthesized in conventional synthestic condition. They include eight binuclear complexes: [Mn2(L2)2py4]·2py (1),[Zn2(L2)2py4]·py (2), [Mn2(L2)2(phen)2] (3), [Zn2(L2)2 (phen)2]·OMF (4), [Cu2(L2)2(DMF)2] (5), [Ni2(L2)2py4]·2py (6), [Ni2(L3)2 (DMF)4]·2DMF (7), [Zn2(L3)2py4]·py (8) (phen: 1,10-phenanthroline, py: pyridine, DMF: N,N-dimethylformamide); two rare asymmetric homometallic trinuclear complexes: [Mn3(L1)3]·1/2H2O (9),[Zn3(L1)3]·1/2H2O (10); one quatrenuclear supramolecular compound: [Ni2(L2)2(DMF)2py2] [Ni2(L2)2(DMF)2(H2O)2] (11) and one coordination polymer: [Cd2(L2)2(4,4'-Bipy)]·CH3OH (12) (4,4'-Bipy: 4,4'-bipyridine). The variable temperature magnetic properties reveal that the overall antiferromagnetic coupling in the asymmetric complex 9. The fluorescent behavior of complexes 2, 4, 10 and 12 were also investigated and discussed in this paper.
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