Effect of Axially Projected Oligothiophene Pendants and Nitro-Functionalized Diimine Ligands on the Lowest Excited State in Cationic Ir(III) bis-Cyclometalates
作者:Kyle R. Schwartz、Raghu Chitta、Jon N. Bohnsack、Darren J. Ceckanowicz、Pere Miró、Christopher J. Cramer、Kent R. Mann
DOI:10.1021/ic202573y
日期:2012.5.7
The novel terthiophene (3T) oligomer 6 and a series of cationic Ir(III) bis-cyclometalates [Ir(C∧N)2(N∧N)]PF69–12 were prepared. The synthesis, characterization, electrochemical, and photophysical properties are reported. The cyclometalating ligands (C∧N) are 2-phenylpyridinato (ppy) or the 3T oligomer (3T-ppy), asymmetrically capped in the 5 and 5″ positions with the ppy and mesityl groups. The diimine
制备了新型的对噻吩(3T)低聚物6和一系列阳离子Ir(III)双环金属盐[Ir(CC N)2(NN N)] PF 6 9 – 12。报告了合成,表征,电化学和光物理性质。环金属化配体(C∧N)是2-苯基吡啶并(ppy)或3T低聚物(3T-ppy),在ppy和mesityl基团的5和5''位上不对称封端。二亚胺配体(N ∧ N)是2,2'-联吡啶(BPY)或4-NO 2联吡啶(4-NO 2 -bpy)。杂化金属-有机络合物11和12携带通过ppy帽连接的3T链,10和12包含NO 2功能化的二亚胺,而9则都不包含。通过单晶X射线衍射对10进行结构表征,证实了关于Ir(III)离子存在NO 2取代基和伪八面体配位几何。循环伏安法突出显示了NO 2取代基的大电子吸收效应,为第一个亚胺中心还原10和12提供了850 mV的向低电位的转移。在11和12的络合物中,带有Ir(III)电荷转移带的3T侧