Spirooxazine-Based Dual-Sensing Probe for Colorimetric Detection of Cu and Fe and Its Application in Drinking Water and Rice Quality Monitoring.

A spirooxazine derivative, (3,3-dimethyl-1-phenethylspiro[indoline-2,3'-naphtho[2,1-][1,4]oxazine]), as a dual-sensing probe for Cu and Fe was synthesized, and its structure was confirmed by H NMR, C NMR, HRMS, and single-crystal X-ray diffraction. The results reveal that the probe is selective to both Cu and Fe through distinct colorimetric responses in acetonitrile. The sensing performance of toward Cu was investigated, and upon addition of Cu, an instant change in color from colorless to bright yellow with a strong absorption band at 467 nm was observed.