Crystallization-induced phosphorescence, remarkable mechanochromism, and grinding enhanced emission of benzophenone-aromatic amine conjugates

• Published in: Chinese chemical letters Vol. 29; no. 10; pp. 1533 - 1536
• Main Authors: Luo, Weijian, Zhang, Yiren, Gong, Yongyang, Zhou, Qing, Zhang, Yongming, Yuan, Wangzhang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.10.2018
• Subjects: Aromatic amines; Benzophenone; Crystallization-induced phosphorescence; Mechanochromism; Room temperature phosphorescence; Mechanochromism; Aromatic amines; Crystallization-induced phosphorescence; Room temperature phosphorescence; Benzophenone
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2018.08.001

Twisted pure organic luminogens based on benzophenone and aromatic amines exhibit both fluorescence and phosphorescence in crystals, while owning merely red-shifted fluorescence at ground amorphous solids. Some of them even demonstrate greatly enhanced emission upon grinding. [Display omitted] Pure organic luminogens with efficient room temperature phosphorescence (RTP) and remarkable mechanochromism are highly desired in view of their fundamental significance and technical applications. Herein, four twisted pure organic luminogens based on benzophenone and aromatic amines were synthesized and their photophysical properties were thoroughly investigated. They exhibit crystallization-induced phosphorescence (CIP), giving bright fluorescence and phosphorescence dual emission in crystals. Upon grinding, they become amorphous and emit predominantly red-shifted fluorescence, demonstrating remarkable mechanochromism. Furthermore, three of them even demonstrate greatly enhanced emission upon grinding, which is rarely observed in twisted D-A structured luminogens.