Helicenoid-based bis-1,2,3-triazole tweezer: Synthesis and selective iodide sensing

Abstract

Novel helicenoid based 1,2,3-triazole tweezer 4 was synthesized using a multistep synthetic protocol with high yields from 2,7-Dihydroxynaphtlene 3 as a precursor. This helicenoid-based bis-1,2,3-triazole tweezer 4 selectively causes non-covalent interaction with iodide anion. The UV-vis absorption exhibited enhancement while fluorescence spectra exhibited significant quenching. ¹H NMR titration showed shift of 1,2,3-triazole C-H signal with an increase in iodide concentration. Association constant of 3.818 × 10⁴ M⁻¹ was recorded for the host interaction with iodide ions. This value of association constant for iodide sensing using 1,2,3-triazole is the best reported so far for hosts with 1,2,3-triazole moiety and suggests that the helicenoid geometry is responsible for this remarkable behavior.

GRAPHICAL ABSTRACT

Keywords:

• Fluorescence
• helicenoid
• iodide sensor
• 1,2,3-triazoles
• tweezer

Supporting information

Procedure for synthesis of compounds 6, 7, 8, and 4 is provided in the supporting information. Full experimental detail, IR, ¹H NMR, and ¹³C NMR, and HRMS spectra can be found via the “Supplementary Content” section of this article’s webpage

Acknowledgments

SBK acknowledges to CSIR-UGC for JRF and SRF funding and Center for Nano Science and Nano Technology, University of Mumbai for UV-vis and Fluorescence study.