Three-Component Reactions for Post-Polymerization Modifications.

Area of Science:

• Polymer Chemistry
• Organic Synthesis
• Catalysis

Background:

• Post-polymerization modification allows for the introduction of new functionalities onto pre-formed polymer chains.
• Copper-catalyzed multi-component reactions (CuMCRs) offer efficient pathways for constructing complex molecules.
• Developing efficient CuMCRs for polymer modification is crucial for creating advanced materials.

Purpose of the Study:

• To employ a copper-catalyzed multi-component reaction (CuMCR) for post-polymerization modification.
• To synthesize polymeric N-sulfonylamidine derivatives from alkyne-functionalized polystyrene.
• To demonstrate the versatility of this method with various amine-containing molecules.

Main Methods:

• Utilized a CuMCR involving terminal alkynes, sulfonyl azides, and amines.
• Applied the reaction to polystyrene with 20 mol% alkyne groups using 4-toluenesulfonyl azide and dihexylamine.
• Employed a Cu(PPh3)3Br/diisopropylethylamine catalyst system.

Main Results:

• The CuMCR on polystyrene proceeded efficiently with near 100% conversion of alkyne groups.
• Polymeric N-sulfonylamidine derivatives were successfully synthesized, confirmed by 1H NMR.
• Structural assignments were validated through model monomeric and polymeric compound synthesis and analysis.

Conclusions:

• A novel and efficient post-polymerization modification strategy using CuMCR has been established.
• The method allows for the synthesis of diverse polymeric N-sulfonylamidine derivatives.
• The reaction's utility was demonstrated with various amines, including dipeptides and crown ethers.