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.

本研究合成了一系列以烷基作为辅助配体的环金属化金(III)配合物（cyclometalated gold(III) complexes）。研究发现，相较于芳基炔配体（arylacetylide ligands）配位的金(III)配合物，该类烷基辅助配体可有效抑制配体到配体电荷转移（Ligand-to-Ligand Charge Transfer, LLCT）激发态的布居，从而提升环金属化金(III)配合物的发射量子产率与发光寿命。此类金(III)烷基配合物在室温溶液中的发射量子产率与发光寿命最高可达0.40与180 μs。通过修饰环金属化配体，可将该类配合物的三重态发光颜色从黄色调谐至天蓝色。