Luminescent Cyclometalated Gold(III) Alkyl Complexes: Photophysical and Photochemical Properties

A series of luminescent
cyclometalated gold­(III) complexes having alkyls as auxiliary ligands
has been prepared. The alkyl ligand was found to effectively increase
the emission quantum yields and lifetimes of luminescent cyclometalated
gold­(III) complexes by circumventing the population of LLCT excited
states that are found in complexes supported by arylacetylide ligands.
These gold­(III) alkyl complexes exhibit emission quantum yields and
lifetimes of up to 0.40 and 180 μs, respectively, in solution
at room temperature. The triplet emission color of these complexes
is tunable from yellow to sky blue by modifying the cyclometalating
ligand.