Efficiently luminescent heteroleptic neutral platinum(ii) complexes based on N^O and N^P benzimidazole ligands

Authors:
Publisher website
Google Scholar
Abstract
A series of new luminescent cycloplatinated(II) complexes (5a–8a and 5b–8b) with formulas Pt(bt)(N^O) and Pt(bt)(N^P) have been synthesized [bt = phenylbenzothiazole, N^O = (2-(1H-benzimidazole)-phenyl)diphenylphosphine oxide derivatives for 1a–4a and N^P = (2-(1H-benzimidazole)-phenyl)diphenylphosphine derivatives for 1b–4b]. The crystal structures of the complexes show distorted square planar geometries around the platinum centers. There are no obvious π–π and Pt–Pt intermolecular interactions in the crystal lattice due to the presence of sterically bulky ancillary ligands. Consequently, these complexes exhibit structured monomeric emissions in the range of 527–540 nm in CH2Cl2 solution. The photoluminescent quantum yields of Pt(bt)(N^O) (5a–8a) in CH2Cl2 solution at room temperature are higher than those of Pt(bt)(N^P) (5b–8b). The above result is well consistent with the crystal structural characteristics of the complexes. The structured emission with microsecond radiative lifetimes and the result of TD-DFT calculations indicate that the emissions of these complexes are mainly attributed to a mixed 3LC-MLCT state.
Funding Information
  • Henan Provincial Science and Technology Research Project (202102210058)
  • National Natural Science Foundation of China (21371154, 21601156)

This publication has 71 references indexed in Scilit: