Electron-Deficient Confined Space: Synthesis and Recognition Properties of a Covalent Molecular Cage Built upon Naphthalene Diimides and Benzene Triimides.

The synthesis of neutral-electron-deficient molecular containers is highly challenging. Nonetheless, the presence of π-acidic units within the confined space of a molecular cage should enable strong anion binding through synergistic anion-π interactions. Here, we report the synthesis of a neutral molecular cage containing five electron-deficient units: two benzene triimide units as roof and floor and three naphthalene diimide units as walls. The study of the cage's conformational isomerism is presented together with the high affinity of the receptor for acetate.