Synthesis And Properties Of A D-π-A Terpyridine Derivative With Flexible Ether Chain And Zn(Ⅱ)Complexes

Terpyridine derivatives have advantages of being various assemblies, flexibly designation, strong coordination ability, withdrawing electronic properties and high stability, so terpyridine derivatives have a wide range of applications in coordination chemistry and the field of opto-electric functional materials. In this dissertation, after reviewing the development and current status of the research for two-photon absorbing materials, two organic ligands and their Zn complexes were designed and synthesized based terpyridine, the major contents were concluded as follow:1.2,2’:6’,2"-terpyridine was selected as an electron acceptor and reacts with the two kinds of aldehydes containing ether oxygen chain by Wittig reaction to introduce a different group in4’-position of2,2’:6’,2"-terpyridine, forming D-p-A type with asymmetric structure of2,2’:6’,2"-terpyridine derivative (terpyridine groups (A)). Styryl acts a p bridge, and the multi-ether group play an electron-donating group (D). The ligands and their intermediates were characterized by1H-NMR,13C-NMR, IR and MS spectroscopies.2. Linear absorption, single-photon fluorescence, time-resolved fluorescence, two-photon fluorescence properties for the L1and L2were carried. The results indicate that absorption and fluorescence emission spectra of L2exhibit redshift; The quantum yield of L1is higher as increase of solvent polarity; L1and L2display large two-photon absorption cross sections and the maximum two-photon absorption were at720nm and760nm, respectively. Density functional theory was used to explain the optical properties of the ligands, and the relationships between the structures and properties were studied.3. Series of complexes of [Zn(L1)2](PF6)2and Zn(Ll)X2, Zn(L2)X2(X=Cl, Br, I, SCN) were synthesized, characterized.[Zn(Ll)2](PF6)2crystallize as a single crystal. Their photophysical properties were systematic studied. The results exhibit that the absorption and emission spectra of the zinc complexes were redshift compared to that of the ligand, the Zn(Ⅱ) ions in the present complexes bring about the quenched single and two-photon fluorescence.