Comprehensive Chiral Spectroscopy Of Compounds And Its Application Research

Interdisciplinarity is the trend of modern scientific development.As the overpass in the cross-disciplines,chirality plays an important role not only in the fields of chemistry and medicine,but also in the materials,environment and life sciences.In recent years,using comprehensive chiral spectroscopy[electronic circular dichroism(ECD),vibrational circular dichroism(VCD),circularly polarized luminescence(CPL)and raman optical activity(ROA)]to determine the absolute configurations of chiral compounds,has become a mainstream method.In this thesis,focusing on the chiral aggregation induced emission(AIE)compounds and chiral Schiff base metal complexes,we employ the comprehensive ECD/VCD spectroscopy combined with the crystal structure analysis and density functional theory(DFT)/time-dependent density functional theory(TDDFT)theoretical calculations to analyze their chiral stereochemical structures,absolute configuration correlation rules with ECD/VCD methods and dominant confor-mations in solid and solution states.We also conduct some preliminary studies of the stereochemical properties of chiral drugs and natural products.The main components of this thesis are presented as follows:The first chapter is the introduction.The applications of comprehensive chiral spectroscopy in the field of chiral AIE compounds,chiral Schiff base metal complexes and chiral drugs are summarized.We focus on the polymorphism,mirror symmetry breaking phenomenon and the mechanism of atropisomer,and briefly introduce the methods to obtain chiral compounds.Finally,the topic basis and research objectives of this thesis are put forward.In the second chapter,we review the principles,measuring methods and applications of ECD,VCD,CPL and ROA spectroscopy and introduce the DFT,TDDFT and exciton coupling theory in brief.In the third chapter,TPE,cis-BETPE,TETPE,TPEQBN,TMTPE and HPS are selected as the research objects.The solid state ECD and VCD spectra combined with crystal structure analysis and DFT/TDDFT calculations are used to deeply study the helical chirality of these six polyphenyl compounds.We first propose the characteristic ECD/VCD spectral peaks in the fingerprint regions to correlate to the helical chirality of the TPE core/HPS core.In the fourth chapter,the comprehensive ECD/VCD spectra armed with DFT/TDDFT calculation are utilized to study the stereochemical structures of chiral Schiff base Ni(II),Cu(?),Mn(?),Co(II)complexes and salen ligands.Their stereocheimical structures include the absolute configuration of the central metal,carbon chirality and chirality of chelating ring conf-ormations.In the fifth and sixth chapters,we take advantage of the comprehensive solid and solution ECD/VCD spectroscopy as well as theoretical calculations to characterize the stereochemical properties of natural products(artemisinin and dihydromyricetin),crystalline drugs linezolid and 1,4-dihydropyridine(1,4-DHPs)derivatives.It is expected that this work can provide a worthy inspiration or method for the future quality controls of the effective enantiomers and chiral crystals in chiral drugs or natural products.In the seventh chapter,the full text is summarized.