Synthesis and properties of fluorinated cyclometalated Ir(III) complexes. Issue 33 (14th August 2020)

• Record Type: Journal Article
• Authors: Wang, Lei; Gao, Zhanming; Liu, Chun; Chen, Yan; Tao, Weitong; Lu, Lu
• Is Part Of: Tetrahedron. Volume 76:Issue 33(2020)
• Publication Date: 2020-08-14
• Subjects: Cyclometalated ir(III) complexes -- Fluorine -- Oxygen sensing; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2020.131390
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: Two new fluorinated cationic cyclometalated Ir(III) complexes have been prepared and fully characterized. The effects of the position of the fluorine on the photophysical, redox properties and oxygen sensing behaviors of the Ir(III) complexes were investigated. The results show that the introduction of a fluorine at the 6-position on the pyridyl ring of the cyclometalating ligand results in a notable blue-shift (91 nm) of the corresponding Ir3 compared to the non-fluorinated Ir1 . While the complex Ir2 with a fluorine at the 5-position of the pyridyl ring shows a red-shift of 21 nm. Moreover, the Φ PL and the phosphorescence lifetime of Ir3 increase effectively than those of Ir1 and Ir2 . The oxygen sensing properties of the complexes were studied in CH2 Cl2 and ethyl cellulose (EC) films, respectively. The fitting results indicate that Ir3 demonstrates the highest oxygen sensitivity both in CH2 Cl2 ( I 0 / I 100 = 235.7) and in an EC film ( I 0 / I 100 = 35.0). Graphical abstract: Image 1 Highlights: Two novel fluorinated cationic cyclometalated Ir(III) complexes were synthesized. The position of fluorine affects the properties of Ir(III) complexes strongly. The 6-fluorinated Ir(III) complex exhibits the highest oxygen sensitivity.