A stable cis-stilbene derivative encapsulated in cucurbit[7]uril

Area of Science:

• Supramolecular chemistry
• Host-guest chemistry
• Organic chemistry

Background:

• Isomerization of stilbene derivatives is a well-known phenomenon.
• Cucurbit[7]uril is a macrocyclic host known for its strong binding capabilities.
• Controlling molecular isomerization is crucial for developing stable functional materials.

Purpose of the Study:

• To investigate the stability of cis-diaminostilbene dihydrochloride when encapsulated in cucurbit[7]uril.
• To understand the role of host-guest interactions in preventing isomerization.
• To explore the potential of cucurbit[7]uril as a stabilizing agent for photoisomerizable molecules.

Main Methods:

• Encapsulation of cis-diaminostilbene dihydrochloride within cucurbit[7]uril.
• Spectroscopic analysis (e.g., NMR, UV-Vis) to monitor isomerization.
• Computational modeling to study host-guest interactions.

Main Results:

• cis-Diaminostilbene dihydrochloride does not isomerize to the trans isomer at room temperature when encapsulated in cucurbit[7]uril.
• Strong hydrogen bonding interactions between the guest's amine groups and the host's portal oxygen atoms were identified.
• These interactions significantly stabilize the cis conformation.

Conclusions:

• Cucurbit[7]uril effectively inhibits the isomerization of cis-diaminostilbene dihydrochloride.
• Host-guest interactions, particularly hydrogen bonding, are key to this stabilization.
• This finding has implications for the design of stable molecular systems and photoresponsive materials.