Synthesis,Structure And Properties Of Transition Metal Fluorescence And Magnetic Complexes

In the past 20 years,the structure and properties of cyanide bridged molecular-based magnets have been concerned.It is well known that the cyanide group with the advantage of transferring the magnetic interaction effectively between the paramagnetic metal ions,revealing the magnetic coupling properties between the paramagnetic metal centers,regulating the molecular topology and predict the molecular magnetic coupling properties,have been widely concerned.The polypyridyl transition metal ruthenium complex system has a very broad application prospect in the field of DNA detection.The research on the novel DNA fluorescent probe of polypyridylium complex provides a theoretical basis for the early diagnosis of cancer.The main research contents are as follows:1.Using tetradentate ligand to occupy the coordination points of the transition metal ions Cr（Ⅲ）and Fe（Ⅲ）at the equatorial position,then introducing cyanide into the axial position of the metal ions,seven cyanide-bridged complexes were obtained by self-assembly with Fourteen-Membered macrocyclic copper（Ⅱ）compounds.Complexes 3,5 and 6 are trinuclear and complexes 1,2,4 and 7 are one-dimensional chains.The magnetic studies show that there is ferromagnetic coupling between adjacent M-Cu（Ⅱ）（M=Cr,Fe）by cyanide-bridged in complex 1,2,3,4 and 7,and there is antiferromagnetic coupling between adjacent Fe（Ⅲ）-Cu（Ⅱ）in complex 5 and 6.2.By using three tetracyanide precursors K₂[M（CN）₄]（M=Ni,Pd,Pt）and a semi-blocked macrocyclic seven-coordinate manganese（Ⅱ）compound for coordination assembly,three new cyanide bridged M^Ⅱ-Mn^Ⅱ complexes have been obtained.By using K₂[M（CN）₄]（M=Ni,Pd）as cyanide precursor and two Mn（Ⅲ）compouds containing bicompartomental Schiff-base ligands as assembling segments,four new cyanide-bridged complexes have been obtained.Complexes 1-3 are one-dimensional chain structures;complexes 4 and 5 are pentanuclear cations and neutral trinuclear structures;complexes 6and 7 are trinuclear structures with different conformations.The magnetic studies show that there is a weak antiferromagnetic coupling between adjacent Mn（Ⅱ）ions in the seven complexes.3.Three new heterobimetallic cyanide-bridged complexes have been designed by self-assembly of new polynitrogen macrocyclic nickel（Ⅱ）compounds and two Schiff-base manganese（Ⅲ）compounds with dicyanyl construction unit K[Ag（CN）₂].Complexes 2and 3 are one-dimensional cationic and neutral single-chain structures respectively,and complex 4 is trinuclear structure.The magnetic studies show that the weak anti-ferromagnetic interaction between neighboring paramagnetic Ni（Ⅱ）or Mn（Ⅲ）ions bridged by the long NC-Ag-CN unit.4.Two new ruthenium（Ⅱ）complexes were obtained by replacing dppz ligand in classical[Ru（L）₂dppz]²⁺（L=2,2’-bipyridine,1,10-phenanthroline,dppz=pyrido[3,2-a:2’,3’-c]phenazine）with[1,2,5]-thiadiazolo-[3,4-f]-[1,10]-phenanthroline（tdzp）.The structure of the complexes 1 was analyzed by single crystal diffraction.The fluorescence of the two complexes and the fluorescence interaction of the two complexes with complementary DNA or mismatched DNA were measured.The results show that the two complexes may not be embedded in DNA,but mismatched DNA quenches the fluorescence of complex 2.