Encapsulation of chromen-4-one Schiff's bases by C-Hexylpyrogallol[4]arene and its structure

•Chromen-4-one Schiff's bases form 1:1 stoichiometric inclusion complexes with C-HPA.•Structure of the inclusion complexes proposed by 2D ROESY NMR.

In this paper, we report the encapsulation of Chromen-4-one Schiff's base derivatives with the host molecule C-Hexylpyrogallol[4]arene. The stoichiometry, binding constant, and the mode of association of the guest molecules with C-Hexylpyrogallol[4]arene are investigated by ultraviolet–visible absorption, steady-state and time-resolved fluorescence, and two dimensional Rotating-frame nuclear Overhauser spectroscopic techniques. The stoichiometry of the host–guest complexes is 1:2. The binding constants of the complexes are of the order of 104. The structures of the host–guest complexes are proposed.

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