One-pot synthesis and structural elucidation of polyfunctionalized quinoxalines and their use as chromogenic chemosensors for ionic species

Abstract

The one-pot synthesis of nine novel polyfunctionalized quinoxaline derivatives starting from l-ascorbic acid is described. Reaction products were obtained in moderate to good yields (65–84%) for an interesting scope of aldehydes after four synthetic transformations. Structural characterization of the molecules was performed by combined NMR (1H, 13C, DEPT-135 COSY and HSQC) techniques, infrared spectroscopy and theoretical calculations. Two selected target-compounds were evaluated as chromogenic chemosensors for ionic species in solution. One of the compounds was effective in the selective detection of Cu2+ in methanol-water 4:1 v/v solution. The other compound was applied as a chemosensor for F− in DMSO and aqueous DMSO solution. Binding mechanisms were proposed based on spectroscopic and theoretical data.