3,6-Disubstituted Carbazole-Based Bisboronic Acids with Unusual Fluorescence Transduction as Enantioselective Fluorescent Chemosensors for Tartaric Acid

Abstract

Carbazole-based bisboronic acids were found to be enantioselective 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.

Colorimetric Sugar Sensing Using Boronic Acid-Substituted Azobenzenes

“…Furthermore, some bis-boronic acids are able to discriminate the chirality of target molecules [26–29]. …”

Observation of Room‐Temperature Deep‐Red/Near‐IR Phosphorescence of Pyrene with Cycloplatinated Complexes: An Experimental and Theoretical Study

“…[12,[27][28][29][30][31][32][33] Investigation of the photophysical properties from a theoretical point of view will be beneficial for the design of new luminophores with predetermined photophysical properties. [12,14,27] The different photophysical properties of the structurally related analogues Pt-1, Pt-2 and Pt-3 are fascinating and we set out to evaluate the different photophysical properties by theoretical calculations.…”

Molecular Rotors as Fluorescent Viscosity Sensors: Molecular Design, Polarity Sensitivity, Dipole Moments Changes, Screening Solvents, and Deactivation Channel of the Excited States

“…[19,20,44,45] To assign the emissive states of rotors 1-11 and to rationalize the photophysics, such as the extremely low fluorescence quantum yields of FMRs 1 and 2 and the increased fluorescence quantum yields of the new rotors (Table 1 and the Supporting Information), DFT/ TDDFT calculations were carried out for all compounds. The geometries of the rotors in the ground state show that the molecules take a coplanar geometry.…”

“…[12,16] However, different from most D-π-A fluorophores, [19][20][21][22][23] the emission of the FMRs is not sensitive to the polarity of the solvent, [5] that is, the emission intensity and the emission wavelength will not change significantly by variation in the polarity of the solvents. [5,6,24] According to the traditional theory of FMRs, viscosity sensitivity and polarity sensitivity are two exclusive properties, that is, those rotors that show solvent-polarity-dependent emission will not show the FMR property and vice versa.…”