title: 1H NMR spectral evidence for a specific host-guest complexation induced charge localization in squaraine dyes.
abstract: [reaction: see text]. Experimental support is provided for the charge localization in squaraines, a class of fundamentally and technologically important organic dyes, by (1)H NMR analysis through a host-guest complexation approach. Specific binding of Ca(2+) ions to the squaraine 2 with a podand sidearm resulted in a charge-localized structure 2a with dramatic shifts and resolution of the proton signals when compared to those of 2.
authors: Photosciences and Photonics Unit, Chemical Sciences Division, Regional Research Laboratory (CSIR), Trivandrum, India. aajayaghosh@rediffmail.com
authors: Ayyappanpillai
authors: A
authors: Ajayaghosh
authors: Easwaran
authors: E
authors: Arunkumar
mesh_terms: D002118:Calcium / Q000737:chemistry; D004396:Coloring Agents / Q000737:chemistry*; D003503:Cyclobutanes / Q000737:chemistry*; D004563:Electrochemistry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*; D013379:Substrate Specificity
chemical_list: D004396:Coloring Agents; D003503:Cyclobutanes; D010636:Phenols; C480596:squaraine; D002118:Calcium