| abstract |
The invention discloses a six-membered spiro-ring rhodamine novel photochromic fluorescent dye containing a urea structure and a preparation method and application thereof. The urea structure-containing six-membered spirocyclic rhodamine novel photochromic fluorescent dye has the general structural formula shown in (I). The preparation method includes the following steps: taking rhodamine compounds, phosphorus oxychloride and dry 1,2-dichloroethane, reacting at 90° C. for 4 hours, cooling to room temperature, removing the solvent, adding dry acetonitrile and sodium azide to saturate The solution was stirred at room temperature, dried, filtered, and the filtrate was reacted at 82°C for 40 min, then primary amine was added, stirred at room temperature, removed the solvent, and purified by silica gel column chromatography. After the photochromic fluorescent dye of the present invention is irradiated with 200-420 nm ultraviolet light, the color of the solution turns red, and an absorption peak appears at 566 nm; at the same time, fluorescence appears at 588 nm, and with the prolongation of the illumination time, the fluorescence intensity increases continuously, and can be Made into ink for anti-counterfeiting. |