title: A Suite of Tetraphenylethylene-Based Discrete Organoplatinum(II) Metallacycles: Controllable Structure and Stoichiometry, Aggregation-Induced Emission, and Nitroaromatics Sensing.
abstract: Materials that organize multiple functionally active sites, especially those with aggregation-induced emission (AIE) properties, are of growing interest due to their widespread applications. Despite promising early architectures, the fabrication and preparation of multiple AIEgens, such as multiple tetraphenylethylene (multi-TPE) units, in a single entity remain a big challenge due to the tedious covalent synthetic procedures often accompanying such preparations. Coordination-driven self-assembly is an alternative synthetic methodology with the potential to deliver multi-TPE architectures with light-emitting characteristics. Herein, we report the preparation of a new family of discrete multi-TPE metallacycles in which two pendant phenyl rings of the TPE units remain unused as a structural element, representing novel AIE-active metal-organic materials based on supramolecular coordination complex platforms. These metallacycles possess relatively high molar absorption coefficients but weak fluorescent emission under dilute conditions because of the ability of the untethered phenyl rings to undergo torsional motion as a non-radiative decay pathway. Upon molecular aggregation, the multi-TPE metallacycles show AIE-activity with markedly enhanced quantum yields. Moreover, on account of their AIE characteristics in the condensed state and ability to interact with electron-deficient substrates, the photophysics of these metallacycles is sensitive to the presence of nitroaromatics, motivating their use as sensors. This work represents a unification of themes including molecular self-assembly, AIE, and fluorescence sensing and establishes structure-property-application relationships of multi-TPE scaffolds. The fundamental knowledge obtained from the current research facilitates progress in the field of metal-organic materials, metal-coordination-induced emission, and fluorescent sensing.
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States.
authors.forename: Xuzhou
authors.initials: X
authors.lastname: Yan
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States.|State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University , Hangzhou 310027, P. R. China.
authors.forename: Haoze
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Chemistry, University at Buffalo , 359 Natural Sciences Complex, Buffalo, New York 14260, United States.
authors.forename: Cory E
authors.initials: CE
authors.lastname: Hauke
authors.affiliation: Department of Chemistry, University at Buffalo , 359 Natural Sciences Complex, Buffalo, New York 14260, United States.
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Cook
authors.affiliation: Department of Chemistry and Biochemistry and Materials Science, Engineering, and Commercialization Program, Texas State University , San Marcos, Texas 78666, United States.
authors.forename: Ming
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States.
authors.forename: Manik Lal
authors.initials: ML
authors.lastname: Saha
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States.
authors.forename: Zhixuan
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States.
authors.forename: Mingming
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Chemistry and Biochemistry and Materials Science, Engineering, and Commercialization Program, Texas State University , San Marcos, Texas 78666, United States.
authors.forename: Xiaopeng
authors.initials: X
authors.lastname: Li
authors.affiliation: State Key Laboratory of Chemical Engineering, Center for Chemistry of High-Performance & Novel Materials, Department of Chemistry, Zhejiang University , Hangzhou 310027, P. R. China.
authors.forename: Feihe
authors.initials: F
authors.lastname: Huang
authors.affiliation: Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Stang