A near-infrared phosphorescent probe for F− based on a cationic iridium(III) complex with triarylboron moieties
作者:WenJuan Xu、ShuJuan Liu、Qiang Zhao、TingChun Ma、Shi Sun、XinYan Zhao、Wei Huang
DOI:10.1007/s11426-011-4359-y
日期:2011.11
In this work, a near-infrared (NIR) phosphorescent probe for F− based on a cationic Ir(III) complex [Ir(Bpq)2(quqo)]PF6 (1) with dimesitylboryl (Mes2B) groups on the cyclometalated C∧N ligands (Bpq) and 2-(quinolin-2-yl)quinoxaline (quqo) as N∧N ligand was designed and synthesized. The excited state properties of 1 were investigated in detail using molecular orbital calculations and experimental methods. Upon excitation, complex 1 shows NIR phosphorescent emission around 680 nm. Interestingly, the complex can be excited with long wavelength around 610 nm. Such long-wavelength excitation can reduce the background emission interference and improve the signal-to-noise ratio. Furthermore, the selective binding between boron atom and F− can give rise to the quenching of emission and realize the near-infrared phosphorescent sensing for F−. We wish that the results reported herein will be helpful for the further design of excellent near-infrared phosphorescent probes based on heavy-metal complexes.
在这项工作中,设计并合成了一种基于阳离子铱(III)配合物[Ir(Bpq)2(quqo)]PF6 (1)的近红外(NIR)磷光探针,该配合物在环金属化C∧N配体(Bpq)上带有二甲苯基硼(Mes2B)基团,以2-(喹啉-2-基)喹喉(quqo)为N∧N配体。通过对1的激发态性质进行了分子轨道计算和实验方法的详细研究。在激发下,配合物1显示出约680 nm的近红外磷光发射。有趣的是,该配合物可用约610 nm的长波长激发。这种长波长激发可以减少背景发射干扰,并提高信噪比。此外,硼原子与F−的选择性结合可以导致发射淬灭,并实现F−的近红外磷光传感。我们希望这里报告的结果将有助于进一步设计基于重金属配合物的优秀近红外磷光探针。