title: Acid/Base and H2PO4(-) Controllable High-Contrast Optical Molecular Switches with a Novel BODIPY Functionalized [2]Rotaxane.
abstract: A novel multifunctional mechanically interlocked switchable [2]rotaxane R4 containing two molecular stations and rotaxane arms terminated with boron-dipyrromethene (BODIPY) fluorophores and its derivatives were synthesized for the first time by CuAAC click reaction. The shuttling motion of macrocycle between the dibenzylammonium and triazolium recognition sites and the distance dependent photoinduced electron transfer process of R4 is demonstrated by utilizing external chemical stimuli (acid/base). Interestingly, the reversible self-assembly process of R4 was recognized by the acid-base molecular switch strategy. Notably, two symmetrical triazolium groups acted as molecular stations, H2PO4(-) receptors, and H-bonded donors. Both [2]rotaxane R4 and thread R2 demonstrated excellent optical responses and high selectivity toward H2PO4(-) ion. The specific motion and guest-host interactions of mechanically interlocked machines (MIMs) were also further explored by quantum mechanical calculations. The thread R2 also demonstrated to enable the detection of H2PO4(-) in RAW 264.7 cells successfully.
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Reguram
authors.initials: R
authors.lastname: Arumugaperumal
authors.affiliation: Center for Interdisciplinary Molecular Science, Department of Applied Chemistry, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Venkatesan
authors.initials: V
authors.lastname: Srinivasadesikan
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Mandapati V
authors.initials: MV
authors.lastname: Ramakrishnam Raju
authors.affiliation: Center for Interdisciplinary Molecular Science, Department of Applied Chemistry, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Ming-Chang
authors.initials: MC
authors.lastname: Lin
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Tarun
authors.initials: T
authors.lastname: Shukla
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Ravinder
authors.initials: R
authors.lastname: Singh
authors.affiliation: Department of Materials Science and Engineering, National Chiao Tung University , Hsinchu 300, Taiwan.
authors.forename: Hong-Cheu
authors.initials: HC
authors.lastname: Lin
mesh_terms: D000468:Alkalies / Q000737:chemistry*; D000818:Animals; D001372:Aza Compounds / Q000737:chemistry*; D001896:Boron Compounds / Q000737:chemistry*; D007700:Kinetics; D051379:Mice; D008968:Molecular Conformation; D057054:Molecular Imaging; D055620:Optical Phenomena; D010756:Phosphoric Acids / Q000737:chemistry*; D066244:Proton Magnetic Resonance Spectroscopy; D000067996:RAW 264.7 Cells; D043862:Rotaxanes / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000468:Alkalies; D001372:Aza Compounds; D001896:Boron Compounds; D010756:Phosphoric Acids; D043862:Rotaxanes; C030242:phosphoric acid
keywords: BODIPY; ESP; H2PO4− ion sensor; PM3 level; and bioimaging; molecular motion; switchable [2]rotaxane