Tetra-n-butylammonium Fluoride as an Efficient Transesterification Catalyst for Functionalizing Cyclic Carbonates and...

Area of Science:

• Polymer Chemistry
• Organic Synthesis

Background:

• Cyclic carbonates are versatile monomers for polymer synthesis.
• Functionalization of polymers often requires harsh conditions, limiting substrate scope.

Purpose of the Study:

• To develop a general method for functionalizing cyclic carbonate monomers and polymers.
• To enable postpolymerization modification of poly(MTC-OC6F5) with alcohols.

Main Methods:

• Transesterification of pentafluorophenyl ester-substituted cyclic carbonate monomers (MTC-OC6F5) using catalytic tetra-n-butylammonium fluoride (TBAF).
• Postpolymerization modification of poly(MTC-OC6F5) via fluoride-mediated transesterification with various alcohols.

Main Results:

• High conversions achieved under mild conditions at room temperature with low TBAF loadings (5 mol %).
• Preservation of sensitive carbonate moieties without Schlenk techniques.
• Quantitative postpolymerization modification of poly(MTC-OC6F5) with diverse alcohols.
• Solid-supported TBAF proved effective for facile workup and purification.

Conclusions:

• TBAF is an effective catalyst for both monomer functionalization and polymer modification.
• This method allows the synthesis of diverse pendant ester-functionalized polycarbonates from a common precursor.
• The developed method overcomes limitations of existing techniques for creating functionalized polycarbonates.