Luminescent Platinum(II) Complexes Containing Cyclometallated Diaryl Ketimine Ligands: Synthesis, Photophysical and Computational Properties
Luminescent Platinum(II) Complexes Containing Cyclometallated Diaryl Ketimine Ligands: Synthesis, Photophysical and Computational Properties
复制标题
含有环金属化二芳基酮亚胺配体的发光铂 (II) 配合物：合成、光物理和计算性能
DOI：
10.1002/ejic.200901159
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发表时间：
2010
影响因子：
2.3
通讯作者：
Pandya S
中科院分区：
文献类型：
--
作者：
Pandya S
A new series of platinum(II) complexes containing cyclometallated diaryl ketimine ligands has been synthesised. The route involves reaction of diaryl ketimines with K[PtCl3(dmso)] to obtaintrans‐[PtCl2(imine)(dmso)] species, which underwent cyclometallation upon heating in toluene to give [PtCl{Ar′(ArC=NH)}(dmso)] complexes12b–17b.N‐Hydroxy andN‐phenyl analogues18band21were also synthesised. In complexes19and20the auxiliary chlorido and dmso ligands were replaced by an acetylacetonato ligand. The photophysical properties of the cyclometallated complexes are reported. The emission bands atλmax≈ 450 and 550 nm are assigned to mixed‐ligand and MLCT states having significant singlet and triplet character, respectively. By varying the structure of the aromatic ligand the efficiency of phosphorescence can be increased to 4.3 % for15b(Ar′ = 1‐naphthyl). Theoretical calculations show that the low‐energy transitions in all the cyclometallated systems involve mainly the frontier orbitals, HOMO and LUMO. These are mixed chlorido–metal–ligand to largely π*‐C=N transitions. Most of the observed phosphorescence data can be explained by the geometric change on going from the S0to the T1states. An organic light‐emitting device has been fabricated by using complex15bas the emissive dopant in a poly(vinylcarbazole) host. Broad electroluminescence spanning the range 500–750 nm was observed.
