Synthesis And Properties Of Containing Of Heavy Metal Ions Of Aromatic Alkyne Oligomer

Aromatic platinum acetylene oligomers containing heavy metal ions and large π electron conjugated system have been extensively researched as a kind of nonlinear optical material in recent years. The prior research results showed that the conjugate small molecules that containing push-pull electronic structures have proper two-photon absorption properties, well the complexes that contain heavy metal ions in general have strong reverse saturation absorption characteristics. In this thesis, a kind of aromatic platinum or mercury acetylene oligomers that contain heavy metal ion and push-pull electronic structure were designed and synthesized in order to get a new kind nonlinear optical materials with the two-photon absorption and the saturation absorption properties at the same time.The aromatic alkyne intermediates were synthesized via the classical Sonogashira reaction catalyzed by Pd(PPh3)2Cl2, CuI and PPh3. Seven platinum or mercury aromatic oligomers with different functional groups were synthesized through classical Hagihara coupling reaction. The target compounds were characterized by 1HNMR, 13 CNMR, 31 PNMR, elemental analysis, mass spectrometry, et al. The maximum absorption peaks of the UV-vis absorption spectra of the target compounds were in the range of 259 nm to 394 nm, which can be assigned to the π- π* transition absorption of the compounds. The π electron delocalization increases with the increasing of the conjugated system of the compounds, which induces a red-shift of the maximum absorption of the compounds. The fluorescent spectra of the target compounds are localized between 328 nm to 496 nm, and the maximum emission peaks of the fluorescent spectra red shift when the conjugated system of compounds increase.The first-order hyperpolarizabilities of the target compounds were determined in the range of 1.56×10-29 cm5/esu to 3.16×10-28 cm5/esu using solvatochromic method. The results showed that the first-order hyperpolarizabilities of the compounds increased when the heavy metal ions were introduced. In addition, the push-pull abilities of the substituent affected the first-order hyperpolarizability strongly. HOMO and LUMO of the target compounds were alculated using Gaussian03 program at the B3 LYP level. The calculation results show that with the increase of aromatic systems, metal dπ orbital contribution to HOMO orbit is relatively less.