Donor–Aniline–Thiophene–Acceptor Emitters: Controlling Charge Transfer and Luminescence Efficiency Through Acceptor Variation

Twelve donor–aniline–thiophene–acceptor chromophores with varying acceptor moieties were synthesized via consecutive lithiation–borylation‐Suzuki‐coupling sequence as potential hybridized localized and charge transfer (HLCT) dyes. Cyclic voltammetry measurements reveal one or two reversible oxidation processes with thermodynamic stability of radical cations. The photophysical properties of these potential HLCT systems display blue to yellow luminescence in the solid state, in solution, and in a poly(methyl methacrylate) film, showing increased emission quantum yield in degassed media up to 68%. Solvatochromism studies reveal an underlying charge transfer character and variable temperature emission spectroscopy accounts for the absence of a thermally activated delayed fluorescence mechanism.