离子型嘧啶铱(Ⅲ)配合物的合成、晶体结构及发光性能

摘要

A series of cyclometalated iridium(Ⅲ) complexes:[(PPM)2Ir(bpy)]PF6 (1),[(MPPM)2Ir(bpy)]PF6 (2),[(DFPPM)2Ir(bpy)]PF6 (3),[(MDFPPM)2Ir(bpy)]PF6 (4) (PPM=2-phenylpyrimidine,MPPM=4,6-dimethyl-2-phenyl-pyrimidine,DFPPM =2-(2,4-difluorophenyl)pyrimidine,MDFPPM =2-(2,4-difluorophenyl)-4,6-dimethylpyrimidine,bpy=2,2'-bipyridine) were synthesized with pyrimidine compounds as cyclometalated ligand and 2,2'-bipyridine as ancillary ligand.New iridium(Ⅲ) complexes were characterized by the NMR and mass spectroscopies,and the single crystal structures of complex 4 was measured.The photophysical properties of the complexes were studied by ultraviolet-visble (UV-Vis) absorption,photoluminescence and time-dependent density functionaltheory (TD-DFT) calculation.X-ray diffraction studies have revealed that complex 4 belongs to monoclinic system with space group of P21/c.A theoretical calculation reveals that the HOMO of 3 and 4 is mainly distributed on the iridium ion and the phenyl group of the cyclometalated ligands,while the LUMO is mainly centered on the ancillary ligand bpy.In CH2Cl2 solution,the iridium(Ⅲ) complexes 1 and 2 exhibit yellow-green emissions with peak at 561 and 572 nm,respectively,while the iridium(Ⅲ) complexes 3 and 4 exhibit green emissions with peak at 501 and 513 nm,respectively.The iridium(Ⅲ) complexes had quantum efficiencies between 6.7％ and 64.0％.CCDC:1585309,4.%以嘧啶类化合物为环金属配体,2,2'-联吡啶为副配体成功制备了4种离子型环金属铱配合物:[(PPM)2Ir(bpy)]PF6 (1),[(MPPM)2Ir(bpy)]PF6 (2),[(DFPPM)2Ir(bpy)]PF6(3),[(MDFPPM)2Ir (bpy)]PF6(4)(PPM=2-苯基嘧啶,MPPM =4,6-二甲基-2-苯基嘧啶,DFPPM=2-(2,4-二氟苯基)嘧啶,MDFPPM=4,6-二甲基-2-(2,4-二氟苯基)嘧啶,bpy=2,2'-联吡啶).配合物的结构通过质谱、核磁进行了表征,测试了配合物4的单晶结构.通过紫外-可见(UV-Vis)吸收光谱、荧光光谱和含时密度泛函理论(TD-DFT)对其光物理性能进行了研究.结果表明:4的晶体的空间构型为单斜,空间群为P21/c;3和4的最高占据轨道(HOMO)主要定域于金属Ir(Ⅲ)和环金属配体的苯环上,最低未占有轨道(LUMO)主要定域于副配体bpy上;配合物在溶液状态下为绿光发射,波长在513～561nm之间,量子效率在6.7％～64.0％之间.