Azulenes exhibiting solid-state fluorescence: synthesis and photophysics of 2-aryl-6-pyrrolidinylazulenes

Abstract

2-Aryl-6-pyrrolidinylazulenes bearing 1,3-diester substituents were synthesized and found to display distinct fluorescence in the solid state. In contrast, the decarboxylated analogues were entirely non-emissive. Photophysical measurements revealed that fluorescence efficiency is primarily governed by the radiative rate constant, while the nonradiative rate remains relatively constant, indicating that activation of the radiative channel underlies the observed emission in the solid state.