Synthesis of 5-Chloro-3-Nitrospiropyran and Recognition of Ag⁺ and Organic Amines

The 5-chloro-3-nitrospiropyran was synthesized and its spectral properties as well as recognitions on metal ions and organic amines were conducted. The results showed that the spiropyran was solvochromic and the closed-loop structure was stable in non-polar solvents while in polar solvents it was the ring-opened structure MC. The spiropyran could specifically recognize Ag⁺ from eighteen common metal ions, and could recognize 16 kinds of organic amines and divide them into four classes.