| Amino acids are a group of biologically important substances. They have strong affinity toward transition metal ions to form coordination compounds with novel structures and functionalities. Recently, the non-covalent week interaction directed self-assembly of amino acid complexes receives a particular emphasis by theoretic and applied chemistry because it concerns the aspects of the interstrands forces in and operation mechanisms of proteins and therefore the design and synthesis and structural investigation of such complexes become the hot topic of coordination chemistry.For the reasons cited, this thesis concentrates on the synthesis and structure determination of transition metal complexes with some amino acids as ligands. All products involved were fully investigated by EA, IR, UV-Vis, TGA and X-ray single crystal diffraction methods. The main points can be stated as follows:1. Eight complexes of phenyliminodiacetic acid (H2L) with 2,2'-bipyridyl (bipy) or benzimidazole (bzim) or 1,10-phenanthroline (phen) as second ligand, [Ni(L)(2,2'-bipy)(H2O)]·2H2O(1), [Cu2(L)2(2,2'-bipy)2](2), [Co(L)(2,2'-bipy)(H2O)]·2H2O(3), [Mn(L)( 2,2'-bipy)(H2O)]·2H2O(4), [Cu2(L)2(phen)2]·2H2O(5), [Co2(L)2(phen)2(H2O)2]·3H2O (6), [Mn(L)(phen)(H2O)]·H2O (7), [Cu4(L)4(bzim)4](8)., were synthesized. IR spectra show that metallation of the acids results in a blue shift of vCO2as and a red shift of vCO2S . The values of ΔvCO2(vCO2<sup>as -vCO2S indicate that the carboxylates are monodentate. Electronic absorption spectra of thecomplexes show a peak in the range of 210-310nm. No decomposition was observed below 200 ℃. X-ray crystallography reveals that the Cu2+ ions in 2, 5 and 8 are 5-coordinated in distorted tetragonal pyramidal and 1, 3, 4, 6 and 7 are 6-coordinated in distorted octahedral geometry. In all these complexes, 3-D hydrogen bond networks and π-π stacking interactions were found.2. A Co3+ complex, [Co(pia)2(2,2'-bipy)]4NO3-·3H2O (Hpia=phenyliminoacetic acid) was synthesized and characterized. Its crystal structure reveals that the Co3+ ion sits in a distorted tetragonal pyramidal coordination environment and that a three-dimensional hydrogen bond network exists among the parent molecules.3. A polymeric Cu2+ complex, {[Cu3(cpida)2(H2O)4]·3H2O}n, was synthesized fromN-(o-carboxyphenyl)iminodiacetic acid (Hscpida). Crystal analysis reveals that the polymers are linear, among which hydrogen bonding occurs to link two chains.
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