title: Selective fluorescence sensing of Cu(II) and Zn(II) using a simple Schiff base ligand: naked eye detection and elucidation of photoinduced electron transfer (PET) mechanism.
abstract: A simple Schiff base compound 2-((cyclohexylmethylimino)-methyl)-naphthalen-1-ol (2CMIMN1O) has been synthesized and characterized by (1)H NMR, (13)C NMR and FT-IR spectroscopic techniques. A significantly low emission yield of the compound has been rationalized in anticipation with photo-induced electron transfer (PET) from the imine receptor moiety to the naphthalene fluorophore unit. Consequently, an evaluation of the transition metal ion-induced modification of the fluorophore-receptor communication reveals the promising prospect of the title compound to function as a chemosensor for Cu(2+) and Zn(2+) ions selectively, through remarkable fluorescence enhancement as well as visual changes. While perturbation of the PET process has been argued to be the plausible mechanism behind the fluorescence enhancement, the selectivity for these two metal ions has been interpreted on the grounds of an appreciably strong binding interaction. Particularly notable aspects regarding the chemosensory activity of the compound is its ability to detect the aforesaid transition metal ions down to the level of micromolar concentration (detection limit being 2.74 and 2.27ppm respectively), along with a simple and efficient synthetic procedure.
authors.affiliation: Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India.
authors.forename: Aniruddha
authors.initials: A
authors.lastname: Ganguly
authors.affiliation: Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India.
authors.forename: Soumen
authors.initials: S
authors.lastname: Ghosh
authors.affiliation: Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India.
authors.forename: Samiran
authors.initials: S
authors.lastname: Kar
authors.affiliation: Department of Chemistry, University of Calcutta, 92, A.P.C. Road, Kolkata 700009, India. Electronic address: nguchhait@yahoo.com.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Guchhait
mesh_terms: D003300:Copper / Q000737:chemistry*; D003510:Cyclohexanes / Q000138:chemical synthesis / Q000737:chemistry*; D004579:Electron Transport; D005453:Fluorescence; D005470:Fluorometry; D008024:Ligands; D008027:Light; D009281:Naphthalenes / Q000138:chemical synthesis / Q000737:chemistry*; D009284:Naphthols / Q000138:chemical synthesis / Q000737:chemistry*; D012545:Schiff Bases / Q000138:chemical synthesis / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: C000604633:2-((cyclohexylmethylimino)-methyl)-naphthalen-1-ol; D003510:Cyclohexanes; D008024:Ligands; D009281:Naphthalenes; D009284:Naphthols; D012545:Schiff Bases; D003300:Copper; D015032:Zinc
keywords: Chemosensor; Fluorophore-receptor communication; PET; Schiff base; Transition metal ions