Distinct luminescent properties between thiophene-S-oxide and Thiophene-S, S-dioxides incorporated ladder-type molecules. (April 2020) - Cao, Jian
Abstract: Oxidized thiophene incorporated molecules show great potential as luminescent materials. However, most works focused on thiophene-S, S-dioxides (TDO) moiety, rarely on thiophene-S-oxide (TO) incorporated molecules. Herein, TO and TDO incorporated ladder-type molecules, namely IDT2O–H and IDT4O–H, have been designed and synthesized to study their luminescent properties. Compared to IDT4O–H, IDT2O–H not only shows stronger and bathochromic fluorescence emission in solution and film states but also exhibits unusual anti-Kasha phosphorescence in film state. The experimental spectra and theoretical calculations demonstrate that the distinct energy levels and orbital features originated from their structures are crucial for the different luminescent properties of IDT2O–H and IDT4O–H. Graphical abstract: Thiophene-S-oxide and thiophene-S, S-dioxides incorporated ladder-type molecules have been designed and their luminescent features are systemically studied. Image 1 Highlights: Thiophene-S, S-dioxides (IDT4O) and thiophene-S-oxide (IDT2O) incorporated ladder-type molecules were synthesized. IDT2O showed stronger and bathochromic photoluminescence emission in both solution and film states. IDT2O film exhibited unusual anti-Kasha phosphorescence emission under ambient conditions.