Syntheses And Properties Of Porphyrin Fused With Aromatic Compounds

Theπ-conjugation of porphyrins was expanded when porphyrins fused with aromatic compounds.On the one hand,the compounds exhibit unique optical properties differing from porphyrin monomer because of the peripheral functional groups,such as red-shifted absorption to near-infrared field.Thus,these compounds have potential application in near-infrared dyes and photodynamic therapy.On the other hand,theπelectrons of porphyrin core were strongly perturbed by the peripheral functional groups,such as theπelectrons transition.Not only the absorption spectra but also the nonlinear optical properties for fused porphyrinoids are largely perturbed because of the expansion of the expansion ofπ-conjugation of porphyrins.Therefore,the porphyrinoids exhibited new promising applications.In the past twenty years,porphyrin chemists synthesized a series of porphyrins fused with aromatic compounds which contained five-membered or six-membered rings.However,they paid little attention to porphyrins fused with aromatic compounds containing seven-membered rings,because seven-membered rings were on sticky position either energetics or dynamics compared with five-membered rings and six-membered rings.To investigate the structures and optical properties of porphyrins fused with aromatic compounds containing seven-membered rings,we designed and synthesized a series of porphyrins fused with biphenyl compounds.The main work of this thesis contained following four parts:(1)The simple reviews of the porphyrins fused with aromatic compounds which contained five-membered or six-membered rings for the past several decades.(2)The synthesis of several meso-biphenyl substituted porphyrins via Suzuki-Miyaura crossing coupling,followed by oxidative coupling and Pd-catalyzed arylation reaction,produced five biphenyl-fused porphyrins.Finally,we optimized the reaction conditions and obtained five biphenyl-fused porphyrins.The synthetic procedures were rather short and the yields were high,such as 51%yield for compound 5Ni.(3)The structure of porphyrin fused with biphenyl containing seven-membered rings were confirmed by ~1H NMR,high resolution mass spectrometry.Some of them have been confirmed by X-ray diffraction analysis.Moreover,the X-ray diffraction analysis of 9Ni-b revealed its curved structure.The dihedral angle between the mean plane of Ni(Ⅱ)porphyrin unit and the seven-membered ring of biphenyl unit were39.88(19)° and 43.93(19)°.And for compound 13Ni-b,the numerical values were 41.27(5)°and 44.00(5)°,respectively.It indicated that structure of biphenyl-fused porphyrins containing seven-membered rings we synthesized has distinct difference from the reported porphyrin fused with aromatic compounds containing five-membered rings and six-membered rings,namely,seven-membered rings with more curved structure.(4)The optical properties were also analyzed by UV/Vis-UV/Vis-NIR absorption spectra.The UV/Vis-NIR absorption spectra of the TM showed red-shifted absorption compared with porphyrin monomer,such 716 nm for compound 9H-a,which demonstrated that extendedπ-conjugation and strong electron interactions between the porphyrin unit and biphenyl unit after oxidative coupling.