Enhanced Quantum Yields by Sterically Demanding Aryl-substituted β-diketonate Ancillary Ligands

Overview

Journal Beilstein J Org Chem

Specialty Chemistry

Date 2018 Apr 7

PMID 29623129

Citations 2

Authors

Rebecca Pittkowski

Thomas Strassner

Affiliations

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Abstract

Luminescent organometallic platinum(II) compounds are of interest as phosphors for organic light emitting devices. Their emissive properties can be tuned by variation of the ligands or by specific electron-withdrawing or electron-donating substituents. Different ancillary ligands can have a profound impact on the emission color and emission efficiency of these complexes. We studied the influence of sterically hindered, aryl-substituted β-diketonates on the emission properties of C^C* cyclometalated complexes, employing the unsubstituted methyl-phenyl-imidazolium ligand. The quantum yield was significantly enhanced by changing the auxiliary ligand from acetylacetonate, where the corresponding platinum(II) complex shows only a very weak emission, to mesityl (mes) or duryl (dur) substituted acetylacetonates. The new complexes show very efficient emission with quantum yields >70% in the sky-blue spectral region (480 nm) and short decay times (<3 μs).

Citing Articles

Functional Materials Based on Cyclometalated Platinum(II) β-Diketonate Complexes: A Review of Structure-Property Relationships and Applications.

Haque A, El Moll H, Alenezi K, Khan M, Wong W Materials (Basel). 2021; 14(15).

PMID: 34361430 PMC: 8347388. DOI: 10.3390/ma14154236.

Recent advances in materials for organic light emitting diodes.

Zysman-Colman E Beilstein J Org Chem. 2018; 14:1944-1945.

PMID: 30112099 PMC: 6071687. DOI: 10.3762/bjoc.14.168.

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