Turn-on fluorescence response upon anion binding to dimesitylboryl-functionalized quaterthiophene.

Addition of CN(-) or F(-) to the B-functionalized quaterthiophene QTB induces a rapid change in the emission color from yellow to blue and blue-green, respectively, accompanied by a strong fluorescence turn-on. Structural analyses and TD-DFT calculations suggest that both the conformation of the conjugated backbone and the nature of the anion have a critical impact. This journal is © The Royal Society of Chemistry 2011