Emerging properties from mechanical tethering within a post-synthetically functionalised catenane scaffold.

Area of Science:

• Supramolecular Chemistry
• Organic Synthesis

Background:

• Close spatial proximity of functional groups leads to emergent properties.
• Covalent tethering is common, but mechanically linked systems are less explored.
• Mechanical bond formation is often a late-stage synthetic step, limiting throughput.

Purpose of the Study:

• To synthesize a versatile bis-azide [2]catenane scaffold.
• To enable post-synthetic functionalization of mechanically interlocked molecules using click chemistry.
• To compare properties of functionalized mechanically interlocked systems with non-interlocked analogues.

Main Methods:

• Synthesis of a bis-azide [2]catenane precursor.
• Copper-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry for post-synthetic modification.
• Electrochemical, photophysical, and photodimerization studies.

Main Results:

• Successful synthesis of a functionalizable bis-azide [2]catenane.
• Demonstration of post-synthetic modification yielding diverse functional catenanes.
• Mechanically interlocked systems exhibit enhanced conformational flexibility compared to covalent analogues.

Conclusions:

• Mechanically interlocked systems offer advantages in conformational flexibility over covalent architectures.
• The developed catenane scaffold provides a platform for accessing diverse functional supramolecular architectures.
• This approach facilitates the development of new functional molecules with unique properties.