含磷酰杂菲侧基的苯乙烯衍生物聚集诱导发光特性及其在过渡金属离子检测中的应用

以2-(6-氧化-6-氢-二苯基(c,e)<1,2>氧杂磷酰基)-1,4-二羟基苯(ODOPB) 为中心结构单元, 通过两步酯化反应, 在两侧分别引入4-戊氧基苯甲酰基和4-乙烯基苯甲酰基, 得到苯乙烯衍生物(MED).由于磷酰杂菲基团的大π共轭结构和极性共同作用, 使得形成聚集体后分子内转动受到限制, 降低了非辐射去活效率, 使 MED在达到一定聚集程度时, 荧光强度成倍增加, 呈现出聚集诱导发光增强(AIEE) 特性. 同时, Pt²⁺, Ru³⁺, Fe³⁺的加入对MED有显著的猝灭效果; 而Fe²⁺只是在形成聚集体过程中才有猝灭效果.

Aggregation-Induced Emission Enhancement Properties of Phosphaphenanthrene-containing Styrene Derivant and Its Application of Detection to Transition Metal Ions

Fluorescence of the organic light-emitting compounds are often quenched when the luminophors are fabricated into solid thin films, which have greatly limited their scope of practical applications. So, it is important to design and synthesize the novel organic luminophors with excellent light emission property in solid state. Phosphaphenanthrene-containing styrene derivant(MED) was synthesized by means of two-step esterification from 2-(6-oxide-6H-dibenz(c,e)<1,2>oxaphos-phorin-6-yl)dihydroxyphenylenes(ODOPB), 4-(pentyloxy)benzoic acid and 4-ethylenebenzoic acid, respectively. And then the compound was characterized by ¹H NMR, FTIR, mass spectra, UV-Vis and PL. When MED aggregates to a certain degree in mixture of water and acetonitrile, the fluorescence strength of MED proportionably increases, which shows obvious aggregation-induced emission enhancement(AIEE) property because the aggregation state of MED restricts the intramlecular rotation of phosphaphenanthrene group based on π-π stacking and polarity interaction between the molecules. Pt²⁺, Ru³⁺, Fe²⁺ and Fe³⁺ ions(1×10^-4 mol/L) can efficiently quench the emission intensity of MED(1×10^-5 mol/L) and higher than those by Pb²⁺, Zn²⁺, Cd²⁺, In²⁺, Co²⁺, Cu²⁺, Ni²⁺ and Ag⁺ ions. The quenching efficiency of Pt²⁺ and Ru³⁺ are the same when they are added into the mixture of water-acetonitrile(90/10, volume ratio) during or after the aggregation state formation of MED. Fe³⁺ shows the highest quenching efficiency to the PL of MAD during aggregation. If being added into the aggregated systems, Fe³⁺ has the same quenching ability to MED. Fe²⁺ only shows its quenching effect on MED during aggregation. This novel phenomenon may enable the molecule to find applications to discriminating chemosensors to detect the transition metal ions.