A new red fluorophore with aggregation enhanced emission by an unexpected "One-step" protocol

In this work, a triphenylamine-benzothiadiazole-based new fluorophore is obtained from a facile "one-step" protocol. A possible reduction mechanism is proposed, and an amine containing α-H plays a key role in the reduction reaction. The resultant product A1H2 exhibits bright red emission in solid state, with an absolute quantum yield of 44.5%. Aggregation induced emission enhancement of A1H2 is also observed with the increased water fraction in THF-H₂O mixture. The nanoparticles of A1H2 reveal good stability and biocompatibility, which are successfully applied in cellular cytoplasm imaging.