Dewar Heterocycles as Versatile Monomers for Ring-Opening Metathesis Polymerization.

Area of Science:

• Polymer Chemistry
• Organic Synthesis
• Materials Science

Background:

• Heterocyclic compounds are versatile building blocks in organic synthesis.
• Ring-opening metathesis polymerization (ROMP) is a powerful technique for polymer synthesis.
• Developing novel monomers for ROMP is crucial for creating advanced materials.

Purpose of the Study:

• To explore the use of readily available heterocycles as precursors for ROMP monomers.
• To synthesize unique polymer backbones with strained cores via photochemical isomerization and ROMP.
• To demonstrate the potential applications of the synthesized polymers in biomedical and conductive materials.

Main Methods:

• Photochemical valence isomerization of pyridones, dihydropyridines, and pyrones to their Dewar isomers.
• Controlled ring-opening metathesis polymerization (ROMP) of the strained Dewar isomers using Grubbs catalysts.
• Post-polymerization modification of polymer backbones containing β-lactam and azetidine cores.

Main Results:

• Successfully generated unique ROMP monomers from common heterocyclic precursors.
• Synthesized polymer backbones containing strained β-lactam and azetidine cores.
• Produced water-soluble β-amino acid polymers with potential as biomedical materials.
• Created highly-soluble poly(acetylene) derivatives from bio-feedstock chemicals for conductive applications.

Conclusions:

• Photochemical isomerization followed by ROMP offers a novel strategy for monomer synthesis.
• The developed method provides access to polymers with unique structural motifs.
• The synthesized polymers show promise for applications in biomedical materials and organic electronics.