Two‐Photon Photochromism of Diarylethene Dimer Derivatives

Abstract

Abstract Photochromic diarylethene dimer derivatives with large two‐photon absorption (TPA) cross‐sections have been designed and synthesized. The derivatives have a D–π–D structure in which indole rings are used as donor units (D) and 1,4‐bis(ethynyl)benzene or 1,4‐bis(ethenyl)benzene as a π‐conjugated chain unit (π). Compound 5 a , which has oxazole rings as one of the aryl groups, showed a TPA cross‐section of 23 GM at 820 nm and exhibited efficient two‐photon photochromic reactivity.