Probing Interactions between Hydrocarbons and Auxiliary Guests inside Cucurbit[8]uril

Area of Science:

• Supramolecular Chemistry
• Host-Guest Chemistry
• Chemical Sensing

Background:

• Cucurbiturils are macrocyclic hosts known for their ability to bind guests.
• Molecular recognition relies on non-covalent interactions.
• Hydrocarbon binding is crucial in various chemical and biological systems.

Purpose of the Study:

• To quantify the binding affinities of hydrocarbons within a cucurbit[8]uril-based host-guest system.
• To investigate the role of CH-π interactions and solvation in molecular recognition.
• To evaluate the selectivity of the system for cyclic hydrocarbons.

Main Methods:

• Measurement of binding affinities in aqueous solution using a {}^{19}F NMR probe.
• Utilizing a cucurbit[8]uril host in conjunction with a ruthenium complex auxiliary guest.
• Analysis of interactions including CH-π and solvation effects.

Main Results:

• The cucurbit[8]uril and auxiliary guest system exhibited high selectivity for cyclic hydrocarbons, including cis- and trans-decalin.
• Binding affinities were successfully measured for 20 different hydrocarbons.
• CH-π interactions and differences in hydrocarbon solvation were identified as significant contributors to binding.

Conclusions:

• The developed supramolecular system demonstrates excellent selectivity for specific hydrocarbon guests.
• The findings highlight the importance of CH-π interactions and solvation in host-guest chemistry.
• This system holds potential for applications in selective hydrocarbon sensing and separation.