作者:Shih-Chun Lo、Ruth E. Harding、Edward Brightman、Paul L. Burn、Ifor D. W. Samuel
DOI:10.1039/b820235d
日期:——
New high triplet energy dendrons based on 1,2-diphenylethylene with and without 2-ethylhexyloxy surface groups have been developed for deep blue phosphorescent iridium(III) dendrimers. The fac-tris[1-methyl-5-(4-fluoro)phenyl-3-n-propyl-1H-[1,2,4]triazolyl]iridium(III)-cored dendrimers, bearing first generation 1,2-diphenylethylene dendrons on the ligand triazolyl and phenyl rings, were prepared in excellent yields, employing Sonogashira cross-couplings and palladium catalysed hydrogenation as the key synthetic steps. Both dendrimers showed good thermal stability although the flexible nature of the dendrons led to the materials having low glass transition temperatures. Dendrimer 15 (without the surface groups) emitted good blue phosphorescence with a solution photoluminescence quantum yield (PLQY) of 46%, Commission Internationale de l'Eclairage (CIE) co-ordinates of (0.15, 0.14) and photoluminescence peaks at 441 and 468 nm. The solution PLQY was 50% higher than the parent iridium(III) complex showing that the high triplet energy of the diphenylethylene dendrons does not quench the luminescence of the iridium(III) complex core. Dendrimer 34, which has the surface groups, had a film PLQY of 49% and CIE co-ordinates of (0.16, 0.19) with PL peaks at 441 and 469 nm.
基于1,2-二苯乙烯的新高三重态能量树状聚合物,分别添加和不添加2-乙基己氧基表面基团,已被开发用于深蓝色磷光铱(III)树状聚合物。这些以fac-tris[1-甲基-5-(4-氟)苯基-3-n-丙基-1H-[1,2,4]三唑基]铱(III)为核心的树状聚合物,具有第一代1,2-二苯乙烯树枝在配体三唑基和苯环上,采用Sonogashira交叉偶联和钯催化氢化作为关键合成步骤,获得了优异的产率。这两种树状聚合物虽然展现了良好的热稳定性,但由于树枝的柔性特性,使材料具有较低的玻璃转变温度。树状聚合物15(不带表面基团)发出了良好的蓝色磷光,溶液光致发光量子产率(PLQY)为46%,国际照明委员会(CIE)坐标为(0.15, 0.14),光致发光峰值分别位于441 nm和468 nm。其溶液PLQY比母体铱(III)复合物高出50%,表明二苯乙烯树状聚合物的高三重态能量并未抑制铱(III)复合物核心的发光。树状聚合物34(带有表面基团)在薄膜中的PLQY为49%,CIE坐标为(0.16, 0.19),光致发光峰值位于441 nm和469 nm。