Dehydroacetic acid derived Schiff base as selective and sensitive colorimetric chemosensor for the detection of Cu(II) ions in aqueous medium

•Synthesis and characterization of Benzohydrazide based chemosensor synthesized for colorimetric sensing of Cu(II) ions using UV-vis, FT-IR, Single Crystal X-ray and 1H-NMR.•Validation of experimental results with theoretical results obtained from DFT, Hirshfeld surface analysis and MEP.•Practical applicability of the probe to number of real water samples collected from different sources.•Absence of any considerable interference from competitive ionic species accounts for excellent selectivity to the probe.