Photo‐Induced Pyramidal Inversion Behavior of Phosphines Involved with the Aggregation‐Induced Emission (AIE) Behavior

Aggregation-induced emission (AIE) is a considerably fascinating phenomenon because of application as a luminescent material in the aggregated state, which explores the large structural change of the molecules in the excited state. Recently it was reported that triphenylphosphine derivatives showed AIE behavior where phosphines undergo potentially large structural change in the excited state. Inspired by this report, we investigated photo-induced pyramidal inversion behavior of phosphines. In photochemical experiments, the prepared P -stereogenic phosphines exhibited photoracemization in the diluted solution, and a negative correlation was observed between the photoracemization and the AIE phenomenon. Theoretical computations revealed that the inversion barrier in the excited state was much smaller than that in the ground state. To the best of our knowledge, this is first report about the photo-induced pyramidal inversion behavior of phosphines, which will provide the new applications that have never been tried before.