Luminescent Metallogels of Bis-Cyclometalated Alkynylgold(III) Complexes
摘要:
A series of luminescent bis-cyclometalated alkynylgold(III) complexes have been synthesized and characterized. Some of the complexes have been demonstrated to exhibit gelation properties driven by pi-pi stacking and hydrophobic-hydrophobic interactions. The gelation properties have been investigated in detail through variable-temperature UV-vis absorption and emission studies, and the morphology of the gels has also been characterized by scanning electron microscopy and transmission electron microscopy.
A series of luminescent alkynylgold(III) complexes containing various tridentate bis-cyclometalating ligands derived from 2,6-diphenylpyridine (R-(CNC)-N-boolean AND-C-boolean AND), [Au(R-(CNC)-N-boolean AND-C-boolean AND)(C C-C6H4-R'] has been successfully synthesized and characterized. Complexes 1 and 6 have been determined by X-ray crystallography. Electrochemical studies show a ligand-centered reduction that originated from the tridentate R-(CNC)-N-boolean AND-C-boolean AND pincer ligands and an alkynyl-centered oxidation. The photophysical properties of the complexes have been studied in detail by electronic absorption and emission studies. Tunable photoluminescence behaviors have been observed, with the emission maxima spanning through the visible region from 476 to 669 nm in dichloromethane at room temperature, and the complexes were also found to be emissive in various media at both room and low temperatures. Transient absorption studies have been conducted to investigate the excited state properties of the complexes. Furthermore, selected complexes have been incorporated into the emissive layer (EML) of organic light-emitting devices (OLEDs) and have demonstrated interesting electroluminescence.