新型硅杂环戊二烯化合物的合成和聚集态发光

Synthesis and aggregation-induced emission of 1,1-dimethyl-3,4-diphenyl-2,5-bis(2′-thienyl)silole

实验合成了一种新型硅杂环戊二烯化合物:1,1-二甲基-3,4-二苯基-2,5-双(2'-噻吩基)silole(TST),利用紫外可见分光光度法和荧光分光光度法对化合物的性能进行研究.TST小分子在稀溶液中基本没有荧光,而在聚集态下呈现非常明亮的荧光发射(聚集诱导发光).TST溶液降低至低温同样能使荧光强度增强到与聚集态相当的程度.实验现象表明:抑制silole分子内2,3,4,5官能团的旋动可有效禁止无辐射跃迁而使荧光增强.由于TST具有固态强发光的优点,可作为发光材料应用于有机电致发光器件中.

The incorporation of siloles in small molecules or polymers is of interest and importance in chemistry and functionalities due to its excellent electronic and optoelectronic properties.A novel compound 1,1-dimethyl-3,4-diphenyl-2,5-bis（2′-thienyl）silole（TST） was synthesized by palladium-catalyzed cross-coupling reaction.The photophysical properties of TST were characterized by ultraviolet（UV） spectra and photoluminescence（PL） spectra.Interestingly,TST was practically nonemissive in solutions,but its aggregates were highly luminescent（＂aggregation-induced emission＂ or AIE）.When the isolated molecules in solutions were cooled to extremely low temperature,they emitted intense light comparable to that in the aggregated state.These results show that deactivation of nonradiative decay by suppression of intramolecular vibrational and torsional motions leads to the increased PL efficiency of TST.The present study suggests that TST is the potential material for fabrication in organic light-emitting devices（OLED）.