title: Selective Host-Guest Co-crystallization of Pyridine-Functionalized Tetraphenylethylenes with Phthalic Acids and Multicolor Emission of the Co-crystals.
abstract: Tetraphenylethylene (TPE) and its derivatives are the most typical and most widely studied organic compounds showing aggregation-induced emission (AIE). Due to their propeller-like structures, V-like clefts exist between the aryl rings, which make them promising host compounds. However, such a possibility is seldom explored. Herein, it is reported that TPE derivatives bearing two or four pyridine rings at the para positions of the phenyl rings (TPE-Pys) can selectively include triangular (Δ-like) m-phthalic acid from a mixture of o-, m-, and p-phthalic acids due to their shape complementary to form host-guest co-crystals, which showed redder emission than the TPE-Pys themselves. The emission of co-crystals 1-5 could be reversibly switched between yellow and red by alternating exposure to HCl and ammonia vapor. The host-guest co-crystals not only exhibited great potential for selectively recognizing and separating m-phthalic acid and as multicolor emission materials, but are also suitable for use as secret ink due to their reversible color change on varying the host-guest interactions.
authors.affiliation: Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.|College of Chemistry and Chemical Engineering, Baoji University of Arts and Sciences, Baoji, 721013, Shaanxi, P.R. China.
authors.forename: Hai-Tao
authors.initials: HT
authors.lastname: Feng
authors.affiliation: Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.
authors.forename: Jia-Bin
authors.initials: JB
authors.lastname: Xiong
authors.affiliation: Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.affiliation: Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.
authors.forename: Wen-Fang
authors.initials: WF
authors.lastname: Feng
authors.affiliation: College of Chemistry and Chemical Engineering, Baoji University of Arts and Sciences, Baoji, 721013, Shaanxi, P.R. China.
authors.forename: Desuo
authors.initials: D
authors.lastname: Yang
authors.affiliation: Key Laboratory for Chemistry of Energy Conversion and Storage Materials, Ministry of Education, School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P.R. China.
authors.forename: Yan-Song
authors.identifier: 0000-0002-1807-4580
authors.initials: YS
authors.lastname: Zheng
keywords: aggregation; aggregation-induced emission; host-guest systems; multicolor emission; piezochromism