The Synthesis,Structures And Properties Of Coordination Complexes Based On ?-and ?-Amino Acids

Amino acids are the active molecules that make up the organism.They are involved in body metabolism and various physiological machine activities.They are also the material basis of life activities and can be divided into protein amino acids and non-protein amino acids.Protein amino acids are the 20 amino acids that make up the protein while non-protein amino acids are mostly similar or substituted derivatives of basic amino acids and?-,?-,?-amino acids.Both protein and non-protein amino acids have multiple physiological functions.Metal elements(Mn,Co,Zn,Cd etc.)are essential trace elements that have special physiological functions to human body which usually exist in the form of complexes.Amino acid metal complexes are widely used in biology,medicine and materials.Therefore,the study of the structures and properties of amino acid metal complexes not only has important academic value and application value,but also plays an important role in exploring the process of life system.In this paper,twelve coordination complexes were obtained by the reaction of three kinds of?-amino acid(?-HL¹,?-HL² and?-HL³)and metal ions,the single crystal structures of three complexes were studied.Seven coordination complexes were obtained by the reaction of two kinds of?-amino acid(?-HL¹ and?-HL²)and metal ions,the single crystal structures of two complexes were studied.One coordination complex was obtained by the reaction of?-amino Acid(L-Glu,L-Gln)and metal ion.The coordination complexes were characterized by X-ray single crystal diffraction analysis,X-ray powder diffraction analysis,IR,elemental analysis and fluorescence spectra.The details are as follows:(1)The complexes Zn(ClO₄)₂-?-HL¹,Zn(CH₃COO)₂-?-HL¹ and Cd-?-HL¹ were synthesized by the reaction of Zn?Cd with?-HL¹ ligand.The achieved two crystals are showed as follows:[Zn(?-HL¹)₄]·(ClO₄)₂·0.5H₂O and[Cd(?-HL¹)₄]·(ClO₄)₂·H₂O.The complexes Zn-?-HL²,Co-?-HL²,Mn-?-HL² and Mg-?-HL² were synthesized by the reaction of Zn,Co,Mn,Mg with?-HL² ligand.The complexes Cu-?-HL³,Zn-?-HL³,Co-?-HL³,Ni-?-HL³ and Mg-?-HL³ were synthesized by the reaction of Cu,Zn,Co,Ni,Mg with?-HL³ ligand.One single crystal was obtained,[Cu(?-HL³)₂(CH₃OH)₂]·2CH₃OH.(?-HL¹=?-Ala,?-HL²=DL-3-Amino-3-phenylpropionic Acid,?-HL³=3-Amino-3-(4-chloropheny)propionic Acid)(2)The complexes Zn-?-HL¹,Mn-?-HL¹ and Cd-?-HL¹ were synthesized by the reaction of Zn,Mn,Cd with?-HL¹ ligand.The achieved two crystals are showed as follows:[Zn₂(?-HL¹)₆]·(ClO₄)₄ and{[Mn₃(?-HL¹)₈(OH)]·(ClO₄)₆}_n.The complexes Zn-?-HL²,Co-?-HL²,Mn-?-HL² and Mg-?-HL² were synthesized by the reaction of Zn,Co,Mn,Mg with?-HL² ligand.In this paper,the magnetic properties of complex Cu(NO₃)₂-?-HL¹obtained from our previous work were studied in detail.The results show that the complex Cu(NO₃)₂-?-HL¹ has antiferromagnetic interaction.(?-HL¹=?-aminobutyric acid,?-HL²=(S)-(-)4-Amino-2-hydroxybutyric Acid)(3)The complex Ca-L-Glu was synthesized by the reaction of Ca with L-Glu.The complex Ca-L-pyroglutamate was synthesized by the reaction of Ca with L-Gln,it is different from the expected and the paper has analyzed the reason.This paper has constructed a variety of complexes by the reaction of?-amino acids,?-amino acids,?-amino acids with metal ions.The synthesis,structures and properties of?-amino acid and?-amino acid metal complexes were mainly studied.It turns out that compare to?-amino acids,?-amino acids and?-amino acids are more difficult to form stable metal complexes.Due to the space factor that when?-and?-amino groups co-coordinate with carboxyl groups to metal ions,they often can not coordinate with chelate coordination mode or even participate in coordination.So the coordination chemistry of?-and?-amino acids are significantly different from that of?-amino acids.Therefore,the amino group of?-and?-amino acids that not participate in the coordination can be an important hydrogen bonding functional groups which provide an important way for the interaction between the molecules.The studies of this paper may provide important experimental and structural information for the study of the coordination chemistry and supramolecular chemistry of ?-,?-and ?-amino acids.