Fluorescent Photochromic Complex of 1,8-Naphthalimide Derivative and Benzopyrane Containing Benzo-18-crown-6 Ether

We present here design, preparation, characterization, and properties of a photochromic supramolecular complex of benzopyran containing benzo-18-crown-6-ether 1 with 4-aminonaphthalimide 2 as a fluorophore. Phototransformation of the supramolecular complex 1⋅2 is accompanied by the appearance of a predominantly open TC form, which is consistent with the monoexponential bleaching curve of an open form at room temperature. Compared with free benzopyran 1, the bleaching rate is increased by 5–6 times in the presence of 2. From a synthetic point of view, varying the components in the supramolecular complex is more preferable to obtain a system with the desired characteristics. Thus, this study demonstrates that the supramolecular approach is promising for systems that contain photochromic and fluorescent components that influence each other.