Synthesis, characterization and sensing properties of donor-acceptor systems based Dithieno[3,2-b;2′,3′-d]thiophene and boron

Two dithieno[3,2-b;2′,3′-d]thiophenes, posessing donor-π-acceptor (D-π-A) character through electron donor triphenylamine and electron acceptor boron, were successfully synthesized. They had large Stokes shifts of 140 and 155 nm and exhibited remarkable solvatochromic behaviors. Emission colors changed from blue to orange in non-polar to polar solvents, respectively. They acted as colorimetric and fluorescent chemosensors with high sensitivity towards fuoride anion, displaying a blue shift from yellow upon addition of TBAF as a result of blocking D-A conjugation.