Synthesis, Simulation, And Properties Of Novel Chiral Phthalocyanine And Subphthalocyanine

Chiral molecular compounds are not only non-substitutable in life processes but playing increasing important roles in the field of unsymmetric synthesis, catalysis, and chiral materials. The development of chirality relies extremely on the chirality formation mechanism as well as novel chiral structures. Phthalocyanines and subphthalocyanines are such a class of multi-pyrrolic compounds with macrocyclic conjugated electron system that exhibit unique optical, electric, or magnetic properties. They are also tunable in structure and electronic property. Chiral structural modification to phthalocyanine and subphthalocyanine lead to optical activity in the UV-vis region, which enables their potential application in chiral self-assembly and chiroptical device. This thesis discusses the design and synthesis of novel chiral phthalocyanine and subphthalocyanines, the relationship between their structures and spectroscopy, and their mechanism of circular dichorism. The following five topics are the main research contents:1. Synthesis and spectroscopic properties of chiral binaphthyl-linked subphthalocyaninesChiral binaphthyl-linked subphthalocyanines (SubPcs) (1) have been prepared by the cyclotrimerization reaction of a phthalonitrile linked with (R)-and (S)-2,2’-binaphthyl in the presence of BCl3, and characterized by various spectroscopies including NMR, electronic absorption, CD, and MCD, as well as electrochemistry.2. Integration of inherent and induced chirality into subphthalo-cyanine analogueConventional conjugated systems are characteristic of only either inherent or induced chirality because of synthetic challenge in combination of chiral segment into the main chromophore. In this work, chiral binaphthyl segment is directly fused into the central chromophore of a subphthalocyanine skeleton, resulting in a novel type of chiral subphthalocyanine analogue (R/S)-1 of integrated inherent and induced chirality. Impressively, an obviously enhanced optical activity is discerned for (R/S)-1 molecules, and corresponding enhancement mechanism is elucidated in detail. The present result paves a new way towards fabrication of chiral materials with giant optical activity and sheds light on their possible application in the chiroptical devices.3. Novel chiral ABBB-type unsymmetrical phthalocyanine. Ring-expansion synthesis, spectroscopic, and electrochemical propertiesA novel chiral ABBB-type unsymmetrical mono(dinaphtho[1,2-e:l’,2’-g]-1,4-dioxocine)-[2,3-b]phthalocyaninato zinc complex Zn[Pc(AB3)] was synthesized via a subphthalocyanine ring-expansion reaction with the addition of an activated chiral binaphthyl-linked phthalonitrile. The resulting pair of phthalocyanine enantiomers has been fully characterized by a series of spectroscopic methods including electronic absorption, CD, MCD, fluorescence, and IR spectroscopy in addition to electrochemistry. The CD measurement with explicit signals over the entire region provides a direct image to the chirality induction from the optically active binaphthyl group to the phthalocyanine chromophore.4. Periphery-hydrogenating effects on the unordinary 14 π-electron delocalized circuits and related electronic properties of subporphyrazine analogs:A density functional theory investigationDensity functional theory method was employed to investigate the electronic properties of two series of subporphyrazine and subphthalocyanine derivatives, namely SubPz, SubPz-1H, SubPz-2H, SubPz-3H, SubPc, SubPc-1H, SubPc-2H, and SubPc-3H. Calculated results show that peripheral hydrogenation essentially changes the delocalized pattern from the common π1414 to limited π1314 or π1214 for SubPz series, and substantially weakens the aromaticity for both SubPz and SubPc compounds. The unordinary delocalized circuit ownsan unstable energy level, and thus gives rise to a notable transformation of geometric configuration, frontier molecular orbital topology, and absorption spectral bands.5. Density functional theory study of pure octupolar porphyrazines with second-order nonlinear optical activityDelicately designed pure octupolar molecular compounds, tetra(triptycene)porphyrazine and its skeleton expanded derivatives have been studied on the basis of density functional theory. The pure octupolar contribution with better isotropy to the second-order nonlinear optical response for these compounds is revealed, with further investigation to the molecular size effects, as well as peripheral polarized substituent influences to the nonlinear optical response.