Reversible Near-Infrared/Blue Mechanofluorochromism of Aminobenzopyranoxanthene
datasetposted on 2015-05-27, 00:00 authored by Masaru Tanioka, Shinichiro Kamino, Atsuya Muranaka, Yousuke Ooyama, Hiromi Ota, Yoshinao Shirasaki, Jun Horigome, Masashi Ueda, Masanobu Uchiyama, Daisuke Sawada, Shuichi Enomoto
Mechanochromic organic molecules (MOMs) that exhibit a large difference of fluorescence wavelength between two states have important potential applications, but few such compounds are known. Here, we report a new MOM, cis-ABPX010, which shows switchable near-IR and blue fluorescence responses. Detailed spectrophotometric and single-crystal X-ray analyses revealed that the near-IR fluorescence is attributable to fluorescence from slip-stacked dimeric structures in crystals, while the blue fluorescence is attributable to fluorescence from the monomer. Switching between the two is achieved by dynamic structural interconversion between the two molecular packing arrangements in response to mechanical grinding and solvent vapor-fuming.