title: Three-Fold C 3-Symmetric Off-On Fluorescent Chemo-Sensors for Fluoride.
abstract: Three novel C 3-symmetric tris-salicylaldimine Schiff base based "off-on" fluorescence sensors have been designed and synthesized. The synthetic approach involves a simple imine bond (C = N) formation between 1,3,5-tris(4'-aminophenyl)benzene (TAPB) and 3,5-substituted salicylaldehydes. The presence of salicylaldehyde units on periphery of the tris-salicylaldimine Schiff bases masks the fluorescence of TAPB core. Interestingly, binding of fluoride ions to the salicylaldehyde units turns the fluorescence "on" in visible region. Fluoride ion detection limits for the present sensors have been calculated to be in the range of 0.17-3.0 ppm, which depends on the nature of the salicylaldehyde units.
authors.affiliation: Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400 076, India. pratapvishnoi.iitb@gmail.com.
authors.forename: Pratap
authors.initials: P
authors.lastname: Vishnoi
authors.affiliation: Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400 076, India.
authors.forename: Saumik
authors.initials: S
authors.lastname: Sen
authors.affiliation: Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400 076, India. naresh@chem.iitb.ac.in.
authors.forename: G Naresh
authors.initials: GN
authors.lastname: Patwari
authors.affiliation: Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai, 400 076, India. rmv@chem.iitb.ac.in.
authors.forename: Ramaswamy
authors.initials: R
authors.lastname: Murugavel
keywords: C 3-symmetric triphenylbenzene; Fluorescence off-on; Fluoride detection; Naked-eye sensor; Schiff base; Stoke’s shift