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Updated: Feb 1, 2026

Light-driven Molecular Motors on Surfaces for Single Molecular Imaging
Published on: March 13, 2019
A benzimidazolyl terpyridine-Fe2+ system and its recognition driven molecular model of a traffic light
Avinash Kumar Sonkar1, Abhishek Rai, Kamini Tripathi
1Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi-221005, India. lmishrabhu@yahoo.co.in.
Abstract:
A new benzimidazolyl terpyridyl ligand (BIT) selectively detects Fe2+, F- and CN- ions in acetonitrile. The Fe2+ complex [Fe(H-BIT)2]·(ClO4)4 (1) displays the fast and selective detection of 2,4,6-trinitrophenol (TNP) with strong binding (log β = 8.51 ± 0.24) and a low limit of detection (1.4 × 10-7 M) among several nitroaromatics. The color of complex 1 changes from purple to red, yellow, and green upon the separate addition of 2,4,6-trinitrophenol and tetrabutylammonium salts of fluoride and cyanide, respectively. The overall color changes thus display a model of a traffic light. The structures of BIT, 1 and [Fe(BIT)2]·(TNP)2 (2) have been well characterized using spectroscopic techniques and single crystal X-ray crystallography.
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