Study on TICT emission of TPE-BODIPY derivatives mediated by methyl group on BODIPY

A series of tetraphenylethene-borondipyrromethene (TPE-BODIPY) derivatives with different numbers of methyl groups on BODIPY cores were designed and synthesized. The intramolecular charge transfer behaviors from donor TPE to accepter BODIPY were investigated. Aggregation-induced emission (AIE), theoretical calculation, single crystal structure and solvent effect all proved that the introduction of methyl group to BODIPY can inhibit the intramolecular charge transfer behavior. Red organic luminescent material 8-TPEBODIPY (TPB) with no methyl groups showing twisted intramolecular charge transfer (TICT) emission peak both in solution and in film state, presents obviously AIE and solvatochromic properties and a large Stokes shifts over 100 nm, which can be employed as a fluorescent sensor for the detection of water in THF.