Separation of Photoactive Conformers Based on Hindered Diarylethenes: Efficient Modulation in Photocyclization Quantum Yields

Endowing both solvent independency and excellent thermal bistability, the benzobis(thiadiazole)‐bridged diarylethene system provides an efficient approach to realize extremely high photocyclization quantum yields (Φo‐c, up to 90.6 %) by both separating completely pure anti‐parallel conformer and suppressing intramolecular charge transfer (ICT). Large hindrance, high efficiency: A novel benzobis(thiadiazole)‐bridged diarylethene system shows excellent thermal bistability and extremely high, solvent‐independent photocyclization quantum yields (Φo‐c, up to 90.6 %). It is characterized by a complete separation of the anti‐parallel conformer and the suppression of intramolecular charge transfer (ICT). EWG=electron‐withdrawing group.