Multicolor Fluorescence Writing Based on Host-Guest Interactions and Force-Induced Fluorescence-Color Memory

• Published in: Angewandte Chemie International Edition Vol. 54; no. 27; pp. 7985 - 7989
• Main Authors: Matsunaga, Yuki, Yang, Jye-Shane
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 26.06.2015; WILEY‐VCH Verlag; Wiley; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Aniline; Chemistry; Chemistry, Multidisciplinary; Color; Dichloromethane; exciplexes; Exposure; Fluorescence; Fumes; host-guest systems; mechanofluorochromism; Phase transitions; Physical Sciences; Science & Technology; Thin films; vapochromism; PENTIPTYCENE-DERIVED OLIGO(P-PHENYLENEETHYNYLENE)S; host-guest systems; fluorescence; MECHANOCHROMIC LUMINESCENCE; exciplexes; mechanofluorochromism; vapochromism; SYSTEMS; INTRACHAIN; EMISSION; POLYMER-FILMS
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201503406

A new strategy is reported for multicolor fluorescence writing on thin solid films with mechanical forces. This concept is illustrated by the use of a green‐fluorescent pentiptycene derivative 1, which forms variably colored fluorescent exciplexes: a change from yellow to red was observed with anilines, and fluorescence quenching (a change to black) occurred in the presence of benzoquinone. Mechanical forces, such as grinding and shearing, induced a crystalline‐to‐amorphous phase transition in both the pristine and guest‐adsorbed solids that led to a change in the fluorescence color (mechanofluorochromism) and a memory of the resulting color. Fluorescence drawings of five or more colors were created on glass or paper and could be readily erased by exposure to air and dichloromethane fumes. The structural and mechanistic aspects of the observations are also discussed. Memorable art: Multicolor fluorescence writing was possible on thin solid films of a pentiptycene–anthracene conjugated system (see picture). This technique relies on the formation of fluorescent exciplexes with aniline vapors and on force‐induced fluorescence color memory. The drawings were erased by blowing air over the surface and by exposure to dichloromethane fumes.