title: Synthesis, Aggregation Induced Emission and Mechanochromic Luminescence of New β-Diketone Derivatives Bearing Tetraphenylene Moieties.
abstract: A series of β-diketone derivatives bearing tetraphenylene (TPE) moieties were synthesized and characterized. Their photophysical properties were investigated systematically via spectroscopic and theoretical methods. All compounds exhibit broad absorption bands between 300 and 450 nm, which are assigned to the1π-π* transition of the conjugated system mixed intramolecular charge-transfer (ICT) transitions. Meanwhile, the emission of these compounds in solution at room temperature (λem= 458 ~ 509 nm) can be attributed to the1π,π*/1ICT state. Introduction of freely rotatable TPE to conventional β-diketone luminophors quenches their light emissions in the solutions, but endows these molecules with aggregation-induced emission (AIE) characteristics in the condensed phase due to the restriction of intramolecular rotation. The spectroscopic studies and theoretical calculations indicate that the photophysical properties of these β-diketone derivatives can be tuned by the appended substituents, which would be useful for rational design of AIE compounds with high solid state luminescence performance. Furthermore, these AIE-active compounds exhibited distinct piezofluorochromic properties and switched reversibly upon grinding-fuming. Their photophysical properties have been investigated with the aim to provide a basis for elucidating the structure-property correlations and developing new multi-stimuli responsive luminescent materials.
authors.affiliation: Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China.
authors.forename: Haijie
authors.initials: H
authors.lastname: Shi
authors.affiliation: Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China. rui.liu@njtech.edu.cn.
authors.forename: Rui
authors.initials: R
authors.lastname: Liu
authors.affiliation: Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China.
authors.forename: Senqiang
authors.initials: S
authors.lastname: Zhu
authors.affiliation: Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China.
authors.forename: Qiqi
authors.initials: Q
authors.lastname: Gong
authors.affiliation: Jiangsu Vocational College of Information Technology, Wuxi, 214153, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Shi
authors.affiliation: Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China.
authors.forename: Xiaolin
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Department of Applied Chemistry, College of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China. zhuhj@njtech.edu.cn.
authors.forename: Hongjun
authors.initials: H
authors.lastname: Zhu
keywords: Aggregation induced emission; Light-emitting materials; Mechanochromic luminescence; Optical property; Synthesis; β-diketone