吸电子基团调控苯基吡啶类铱配合物的光物理和氧敏感性能  

Photophysical properties and oxygen sensitivity of phenylpyridine-type iridium(Ⅲ)complexes with electron-withdrawing groups in the cyclometalating ligand

作　　者：于洪翠 于波 宋亚娇 李佳伟 YU Hongcui;YU Bo;SONG Yajiao;LI Jiawei(College of Chemistry and Materials Science,Inner Mongolia Minzu University,Tongliao 028000,Inner Mongolia,China)

机构地区：[1]内蒙古民族大学化学与材料学院,内蒙古通辽028000

出　　处：《贵金属》2024年第3期33-38,45,共7页Precious Metals

基　　金：内蒙古自治区青年教师科研创新能力提升计划(GXKY22119);内蒙古自然科学基金(2019BS02009);内蒙古高等学校科学研究项目(NJZY20116);内蒙古民族大学博士科研启动资金(BS425,BS397);在校优秀学生基本科研能力提升计划(GXKY22234)。

摘　　要：以1,10-邻菲罗啉为N^N辅助配体,2-苯基吡啶为C^N主配体,在2-苯基吡啶主配体中苯基的2,4位引入吸电子基团氟原子、在2-苯基吡啶主配体中苯基的2,4位引入氟同时3位引入吸电子的二苯基膦氧基团,合成出3个阳离子型苯基吡啶类铱配合物Ir1-Ir3并进行了表征。通过紫外-可见吸收光谱、发射光谱、循环伏安法和密度泛函理论计算对配合物Ir1-Ir3的光电性能进行了研究,将配合物Ir1-Ir3置于不同氧气浓度的乙腈溶液中测试了氧敏感性能。结果表明,配合物Ir1-Ir3在二氯甲烷中的最大发射波长分别为570、506和470 nm,量子产率分别为23%、35%和56%,起始氧化电位分别为1.20、1.51和1.87 V。与Ir1相比,吸电子的氟和二苯基膦氧基团的引入降低相应铱配合物Ir2和Ir3的HOMO能级更显著,从而表现为能隙增大,发射峰蓝移。配合物Ir1-Ir3的发射光谱可被氧气猝灭,而且Ir3猝灭效果最好,可作蓝绿光氧敏感探针,猝灭常数K_(sv)=0.14 Torr^(-1)。To evaluate the effect of electron-withdrawing groups on iridium(Ⅲ)complexes,three cationic iridium(Ⅲ)complexes Ir1-Ir3 were synthesized by using 1,10-phenanthroline as the N^N ancillary ligand and 2-phenylpyridine(ppy)or two ppy derivatives as the C^N cyclometalating ligand.The two derivatives are a ppy molecule containing fluorine and a ppy molecule containing both fluorine and diphenylphosphoryl unit,respectively,corresponding to Ir2 and Ir3.The photophysical and electrochemical properties of the ppy-type complexes were studied by UV-Vis absorption spectra,emission spectra and cyclic voltammetry along with theoretical calculations.The oxygen sensitivity was tested in acetonitrile solution with different oxygen concentrations.The results show that the emission peaks of complexes Ir1-Ir3 in dichloromethane solution are 570,506 and 470 nm,respectively,with a quantum yield of 23%,35%and 56%.The onset oxidation potentials were measured to be 1.20,1.51 and 1.87 V.The introduction of electron-withdrawing fluorine and diphenylphosphoryl groups affects the HOMO energy level of the corresponding complexes Ir2 and Ir3,showing a larger energy gap than Ir1 and resulting in the blue-shifted emission.The emission of complexes Ir1-Ir3 can be quenched by oxygen,and the introduction of electron-withdrawing groups enhances the quenching effect.For Ir3,the Stern-Volmer quenching constant K_(sv) value is 0.14 Torr^(-1),suggesting the complex has the potential application as a blue-green type oxygen probe.

关 键 词：铱(Ⅲ)配合物 吸电子基团 光电性能 密度泛函理论 氧敏感性 

分 类 号：O627.8[理学—有机化学]