title: Design and synthesis of a new organic receptor and evaluation of colorimetric anion sensing ability in organo-aqueous medium.
abstract: A new organic receptor has been designed and synthesized by the combination of aromatic dialdehyde with nitro-substituted aminophenol resulting in a Schiff base compound. The receptor exhibited a colorimetric response for F(-) and AcO(-) ion with a distinct color change from pale yellow to red and pink respectively in dry DMSO solvent and yellow to pale greenish yellow in DMSO:H2O (9:1, v/v). UV-Vis titration studies displayed a significant shift in absorption maxima in comparison with the free receptor. The shift could be attributed to the hydrogen bonding interactions between the active anions and the hydroxyl functionality aided by the electron withdrawing nitro substituent on the receptor. (1)H NMR titration and density functionality studies have been performed to understand the nature of interaction of receptor and anions. The lower detection limit of 1.12ppm was obtained in organic media for F(-) ion confirming the real time application of the receptor.
authors.affiliation: Supramolecular Chemistry Laboratory, National Institute of Technology Karnataka (NITK), Surathkal 575025, Karnataka, India.
authors.forename: P
authors.initials: P
authors.lastname: Srikala
authors.affiliation: Department of Physics, National Institute of Technology Karnataka (NITK), Surathkal 575025, Karnataka, India.
authors.forename: Kartick
authors.initials: K
authors.lastname: Tarafder
authors.affiliation: Supramolecular Chemistry Laboratory, National Institute of Technology Karnataka (NITK), Surathkal 575025, Karnataka, India. Electronic address: darshak_rtrivedi@yahoo.co.in.
authors.forename: Darshak R
authors.initials: DR
authors.lastname: Trivedi
keywords: Colorimetric anion sensor; Organic receptor; Organo-aqueous; Real time analysis