The development of aryl-substituted 2-phenylimidazo[1,2-a]pyridines (PIP) with various colors of excited-state intramolecular proton transfer (ESIPT) luminescence in the solid state
作者:Toshiki Mutai、Tatsuya Ohkawa、Hideaki Shono、Koji Araki
DOI:10.1039/c6tc00376a
日期:——
electron-withdrawing nature of the para-substituent on the aryl group increases. Varying the substitution position is also an effective tuning method, because the ESIPT luminescence wavelength is in the order 6-aryl < 8-aryl < 6,8-diaryl. Although the quantum yields of these compounds are quite low in organic solutions (Φ ∼ 0.01), they generally display a much stronger ESIPT luminescence in the solid state. For all
已经开发了一系列基于2-苯基咪唑并[1,2- a ]吡啶(PIP)的固态发光染料,其显示出从蓝色到红色的多种发光颜色。而2'-甲氧基PIP(2'MeOPIP,10)显示蓝色发光,而2'-羟基PIP(HPIP,1)则在500 nm左右具有大斯托克斯位移的发射,这被称为激发态分子内质子转移(ESIPT) )发光,只需通过Pd催化的交叉偶联反应将芳基引入HPIP即可将其从蓝绿色变为红色。结果表明,ESIPT发光的能量作为的吸电子性质降低对芳基上的-取代基增加。改变取代位置也是一种有效的调整方法,因为ESIPT的发光波长为6-芳基<8-芳基<6,8-二芳基。虽然这些化合物的量子产率是相当低的在有机溶液(Φ〜0.01),但它们通常显示在固态强得多ESIPT发光。对于除9之外具有长C 6的所有化合物-烷基链,稀冷冻基质和固态中相似的发射特性表明,即使通过结晶学证实了HPIP核的π堆积基序和引入的芳基,