Highly selective phosphorescent chemosensor for fluoride based on an iridium(III) complex containing arylborane units.
A new phosphorescent iridium(III) complex [Ir(Bpq)2(bpy)](+)PF6(-) based on cyclometalated ligands (Bpq) containing a dimesitylboryl group was synthesized and characterized by photophysical and electrochemical studies. The excited-state properties of Bpq and [Ir(Bpq)2(bpy)](+)PF6(-) were investigated using molecular orbital calculations. Importantly, both Bpq and [Ir(Bpq)2(bpy)](+)PF6(-) could be used as highly selective chemosensors for a fluoride anion (F(-)) detected by the naked eye, owing to the interaction of the dimesitylboryl group (BMes2) with F(-). For the Bpq ligand, a red shift of the emission spectrum was observed upon the addition of F(-), which could be attributed to an excited-state switch from a pi-pi* transition to a charge-transfer transition upon complexation with F(-). The addition of F(-) to a solution of [Ir(Bpq)2(bpy)](+)PF6(-) induced a change in the solution color from yellow to orange-red and phosphorescent quenching, indicating that [Ir(Bpq)2(bpy)](+)PF6(-) could act as an excellent ON-OFF-type phosphorescent chemosensor for F(-).
Zhao
Qiang
Q
Department of Chemistry & Laboratory of Advanced Materials, Fudan University, Shanghai 200433, People's Republic of China.
Li
Fuyou
F
Liu
Shujuan
S
Yu
Mengxiao
M
Liu
Zhiqiang
Z
Yi
Tao
T
Huang
Chunhui
C
D001880:Boranes / Q000737:chemistry*; D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004563:Electrochemistry; D005459:Fluorides / Q000737:chemistry*; D007495:Iridium / Q000737:chemistry*; D049408:Luminescent Agents / Q000138:chemical synthesis* / Q000737:chemistry; D055095:Optics and Photonics; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D012680:Sensitivity and Specificity
D001880:Boranes; D049408:Luminescent Agents; D009942:Organometallic Compounds; D007495:Iridium; D005459:Fluorides