Room-temperature phosphorescence of cucurbit[7]uril recognized naphthalimide derivative

•A novel room-temperature phosphorescence system via host-guest interaction was constructed.•The phosphorescence emission and lifetime of the system were thoroughly investigated.•The binding pattern and constant between cucurbit[7]uril and guest was determined.

It is well known that most purely organic molecules give out no room-temperature phosphorescence due to consuming the energy of molecular vibration, inefficient spin-orbit coupling and easy-quenched radiation relaxation process. Room-temperature phosphorescence emission was presented by the host-guest interactions between cucurbit[7]uril and a naphthalimide derivative 2-(4-aminobutyl)-6-bromo-1H-benzo[de]isoquinoline-1,3(2H)-dione. This cucurbit[7]uril recognized supramolecular system can emit room-temperature phosphorescence signal in aqueous solution, as well as the 4-bromo-1,8-naphthalic anhydride polymer/cucurbit[7]uril system. The conformation of the complex was established by 1H-1H ROESY NMR techniques. The binding patterns and constant of this supramolecular system were well defined, and its photophysical and photochemical properties found in detail as well.

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