Cucurbiturils substituted on the methylene bridge

Area of Science:

• Supramolecular Chemistry
• Macrocyclic Chemistry

Background:

• Cucurbiturils are macrocyclic hosts known for their unique binding properties.
• Previous cucurbituril derivatives have shown diverse applications in molecular recognition and self-assembly.
• Functionalization of cucurbiturils is key to tailoring their properties.

Purpose of the Study:

• To synthesize a cucurbit[6]uril (CB[6]) derivative with a substituent on a single methylene bridge.
• To investigate the self-assembly behavior of this novel monosubstituted CB[6].
• To evaluate the impact of the substituent on the guest binding affinity of CB[6].

Main Methods:

• Synthesis of monosubstituted cucurbit[6]uril via a novel route.
• Solid-state characterization to determine self-assembly behavior (e.g., X-ray diffraction).
• Binding studies using a series of alkylammonium salts to measure host-guest interactions.

Main Results:

• Successful preparation of the first monosubstituted cucurbit[6]uril (CB[6]).
• The monosubstituted CB[6] forms a cyclic tetramer in the solid state.
• The substituent had a minor influence on the binding affinity of the macrocycle for alkylammonium guests.

Conclusions:

• Monosubstituted cucurbit[6]urils are accessible and exhibit predictable self-assembly.
• The functionalization of CB[6] at the methylene bridge minimally affects its core binding capabilities.
• This work opens avenues for designing tailored cucurbituril-based supramolecular systems.