Carbazole-based bisboronic acids were found to be enanti-oselective fluorescent sensors for tartaric acid. The fluorescence response toward the enantiomers of tartaric acid at neutral pH displayed enhancement/diminishment. The sensor displays an unusual fluorescence intensity-pH relationship with diminished emission at acidic pH but enhanced emission at basic pH. Photoinduced electron transfer (PET) from the fluorophore to the protonated amine/phenylboronic acid unit is proposed to be responsible for this effect, which is rationalized by density functional theory (DFT) calculations.
- Electron transitions
- Density functional theory
Han, F., Chi, L., Liang, X., Ji, S., Liu, S., Zhou, F., Wu, Y., Han, K., Zhao, J., & James, T. D. (2009). 3,6-Disubstituted carbazole-based bisboronic acids with unusual fluorescence transduction as enantioselective fluorescent chemosensors for tartaric acid. Journal of Organic Chemistry, 74(3), 1333-1336. https://doi.org/10.1021/jo8025669