Phosphorescent cyclometalated platinum(ii) complexes with phenyldiazine N^C ligands. Issue 7 (25th January 2023)

• Record Type: Journal Article
• Authors: Hruzd, Mariia; Kahlal, Samia; le Poul, Nicolas; Wojcik, Laurianne; Cordier, Marie; Saillard, Jean-Yves; Rodríguez-López, Julián; Robin-le Guen, Françoise; Gauthier, Sébastien; Achelle, Sylvain
• Is Part Of: Dalton transactions. Volume 52:Issue 7(2023)
• Page Start: 1927
• Page End: 1938
• Publication Date: 2023-01-25
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2dt03690h
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Pt(ii ) complexes bearing phenyldiazine N^C ligands as well as chloride and azaheterocyclic ancillary ligands were successfully modified, yielding interesting luminophores with a wide range of emission color. Abstract : A series of phosphorescent platinum(ii ) complexes containing various phenyldiazine-type bidentate N^C ligands have been successfully synthesized and characterized. Structural modifications have been made to bidentate cyclometalating ligands regarding the nature of the diazine ring (pyrimidine, pyrazine and quinazoline), the substituent groups at the C4 position of the pyrimidine ring (OCH3, CF3 ) and the EDGs at the para position of the Pt atom (OCH3, Ph, NPh2, carbazol). In addition, the electronic properties of the azaheterocyclic ancillary ligand have been modulated in this series of complexes (pyridine, 4-methoxy-pyridine or pyrimidine). X-ray diffraction studies have been performed on three complexes, revealing Pt(ii ) ions in a distorted square-planar geometrical environment with no Pt(ii )⋯Pt(ii ) interactions but with moderate π–π interactions in the solid-state structure. Electrochemical and computational studies suggest a ligand-centered reduction on the diazine ligands with, in some cases, additional contribution from the azaheterocyclic ancillary ligand, whereas oxidation occurs on the Pt-phenyl ring substituent moieties. All complexes exhibit phosphorescence emission ranging from green to red/near-infrared, both in solution and in the solid state. Complexes bearing a 2-(3-methoxyphenyl)pyrimidine ligand show the best PLQY of the series, up to 52% in a CH2 Cl2 solution and 20% in the solid state. Furthermore, the solid state PLQY of one of the near-infrared emitting phenylquinazoline complex has been found to be 6%.