A highly selective ratiometric chemosensor for Ni2+ in a quinoxaline matrix†
Abstract
The monohydrazone of quinoxaline aldehyde (HOQA) is found to be a ratiometric and colorimetric probe for Ni2+. HOQA shows a remarkable color change from colorless to yellow upon specific and selective binding to nickel that can be identified even by the naked eye. The cation recognition property of the receptor is monitored by UV-vis and 1H-NMR titrations and also by DFT (Density Functional Theory) and TD-DFT (Time Dependent Density Functional Theory) calculations.