Mechanofluorochromism of carbazole-type D¨C¦Ð¨CA fluorescent dyes

详细信息    查看全文

• 作者：Yousuke Ooyama ; Naoya Yamaguchi ; Shogo Inoue ; Tomoya Nagano ; Eigo Miyazaki ; Hiroshi Fukuoka ; Ichiro Imae ; Kenji Komaguchi ; Joji Ohshita ; Yutaka Harima  ; ;   ; ^{harima@mls.ias.hiroshima-u.ac.jp}
• 刊名：Tetrahedron
• 出版年：2012
• 出版时间：14 January 2012
• 年：2012
• 卷：68
• 期：2
• 页码：529-533
• 全文大小：951 K

文摘

We have newly designed and synthesized unsymmetrical carbazole-type D¨C¦Ð¨CA fluorescent dyes. The dyes show a bathochromic shift-type mechanofluorochromism (MFC): grinding of as-recrystallized dyes induces a bathochromic shift of fluorescent color and the fluorescent color is recovered by heating or exposure to solvent vapor. In order to clarify the MFC mechanism for the carbazole-type D¨C¦Ð¨CA fluorescent dyes, time-resolved fluorescence spectroscopy, X-ray powder diffractometry, single-crystal X-ray structural analysis, IR spectroscopy, and differential scanning calorimetry are performed before and after grinding of the solids. On the basis of experimental results and semi-empirical molecular orbital calculations (AM1 and INDO/S), we have revealed that the MFC is attributed to a reversible switching between crystalline and amorphous states with changes of intermolecular hydrogen bonding and ¦Ð¨C¦Ð interaction.