Structures And Preliminary Methodology On The Integrated Chiroptical Spectroscopy Of Chiral N₂O₂-Type Schiff Base Metal Complexes

Chiral Schiff base metal complexes have been wildly applied in the asymmetric catalysis and chiral functional materials areas.They can be used as model compounds in the fundamental research of electronic circular dichroism(ECD)and vibrational circular dichroism(VCD)spectroscopy due to the diversity of their chiral chromophores and coordination stereo-structures.This thesis mainly focuses on the chiral Schiff base Ni(?)and Cu(?)complexes,deeply study their chiral coordination spatial structures,dominating conformations as well as the correlation between their absolute configurations and comprehensive solid or solution state ECD/VCD spectroscopy.The chiral schiff base Cu(?)complexes which possess helical supra-molecular structures were preliminarily discussed.Main contents containing six sections are as follows:Chapter 1 introduces the origin of Schiff-base,salen ligands and summarizes the different definition rules of the absolute configuration of four-coordinate metal complexes with N2O2-type Schiff base ligands;introduces four levels of chirality in the chiral Schiff base metal complexes and focus on the helical supramolecular structures;then reviews the correlation rules between their absolute configurations and integrated chiroptical(ECD/VCD)spectroscopy.Finally,the selected topics basis and research target of this dissertation is briefly presented.In chapter 2,chiral Schiff-base ligands and their metal Ni(II)and Cu(II))complexes were synthesized.They were characterized by element analysis,mass spectra,multiple ECD/VCD spectra,and X-ray single crystal diffraction.In chapter 3,the crystal structures of[Cu(dha-R,R-chxn)],[Cu(dha-S,S-chxn)],[Cu(dha-R,R-dpen)],[Cu(dha-S,S-dpen)],[Cu(dha-R,R-binam)]and[Cu(dha-S,S-binam)]were characterized.The chiral supramolecular self-assemblies in the formation of chiral coordination polymers with one-dimensional helical chains for chiral[Cu(dha-R,R/S,S-en)](en = chxn and dpen)and their integrated chiroptical spectroscopy were preliminarily studied as well.In chapter 4,the correlation between the multiple chiropticai spectroscopy and absolute configurations of four-coordinate chiral Schiff base Cu(II)complexes were discussed.However,the different ECD correlation rule we have proposed was applied to the related chiral schiff base Ni(II)complexes.In chapter 5,based on the above study,the solution ECD spectra of[Cu?(bsal-R,R/S,S-chxn)]+ was characterized for the first time and compared with those of[Ni?(bsal-R,R/S,S-chxn)].In chapter 6,the thesis is concluded with a brief summary.