An Uncommon Solid-State Fluorophore

Significance

Fluorophores such as 1 and 2 were synthesized in moderate overall yield. Structural isomers 1 and 2 were obtained in a 3:1 ratio; however, N-alkylation of the carbazole moiety was found to alter the product ratio in favor of the latter isomer. While both fluorophores displayed broad emission curves in the range of 500-700 nm, the quantum yield of compound 1 is near unity whereas that of compound 2 is only 0.17. N-Alkylated derivatives of both isomers display solid-state fluorescence spectra that differ minimally from solution curves, indicating that these fluorophores do not aggregate in the solid state.