合成了8个具有不同结构的羟基苯基苯并咪唑类荧光化合物,通过HNMR,IR对其进行了结构表征,并研究了它们在甲醇溶液中的光谱性质及取代基对光谱性质的影响.该类化合物的荧光量子产率在0.006~0.75之间,Stokes位移大(〉117nm)。实验结果表明,化合物上所连取代基的性质对其光谱有显著影响,具有推电子基团的羟基苯基苯并咪唑类化合物在光激发下出现荧光双发射峰,而具有吸电子基团的化合物在光激发下仅出现激发态质子转移荧光发射峰,表现出Stokes位移大和荧光量子产率高的优点。
A series of 2-(2,-hydroxyphenyl) benzimidazole derivatives with different substitu- ents were synthesized, and their structure were confirmed by 1H NMR and IR. The spectroscopic properties of their solution in methano turn yield (the maximum is 0. 75) and were investigated. These compounds exhibit high quan arge stokes shift ( ll7nm,in methanol). Furthermore, the property of substituents has significantly influence on their fluorescence properties. Generally, benzimidazole derivatives with electron-donating group show normal emission and tautomer emission in the excited state, while that with electron-withdrawing group only show tautomer e mission.