Reversible Vapochromic Luminescence Accompanied by Planar Half‐Chair Conformational Change of a Propeller‐Shaped Boron β‐Diketiminate Complex

Leakage of volatile organic compounds (VOCs) is one the most severe industrial problems, because it can cause environmental pollution, global warming, fire, and explosion. Hence, visualization leakage an essential technology to detect at early stage. Molecular crystals, fluorescence color which be changed by exposure VOCs could potentially serve as sensing materials for realizing rapid facile VOC detection. However, these usually require harsh conditions, such heating or a vacuum, recover their initial phases reuse. Therefore, remains challenge obtain completely reversible systems without energy-consuming recycling processes. Herein, change from crystals propeller-shaped boron β-diketiminate complex reported. The was crystallized in distinct crystalline having different luminescent colors. Importantly, were interconverted very rapidly (time constant <60 s) repeatedly upon vapors appropriate VOCs. small energy differences between conformers lead this pseudopolymorphic behavior. This finding applied development further eco-friendly based on four-coordinated complexes.