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A Novel Nicotinamide Adenine Dinucleotide Correction Method for Intracellular Ca2+ Measurement with Fura-2-Analog in Live Cells
Published on: September 20, 2019
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Living Polymerization of 2-Ethylthio-2-oxazoline and Postpolymerization Diversification
You-Chi Mason Wu1, Timothy M Swager1
1Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States.
Journal of the American Chemical Society
|August 1, 2019
Summary
Researchers developed a versatile method for creating precision nanomaterials. This polymer modification technique allows for diverse polyurea and polythiocarbamate synthesis via a novel substitution platform.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Synthesis
Background:
- Living polymerization enables the synthesis of polymers with controlled architectures.
- Postpolymerization modification is crucial for tailoring polymer properties and creating advanced materials.
- Precision nanomaterials require sophisticated synthetic strategies for controlled functionalization.
Purpose of the Study:
- To introduce a novel living polymerization method for synthesizing polythiocarbamates.
- To establish a versatile postpolymerization modification platform for polythiocarbamates.
- To demonstrate the application of this platform in creating functionalized block copolymers.
Main Methods:
- Living cationic ring-opening polymerization of 2-alkylthio-2-oxazoline.
- Oxidation of the polythiocarbamate sulfur atom to a sulfonyl group (SO2).
- Nucleophilic substitution reactions with N- and S-nucleophiles.
Main Results:
- Successful synthesis of polythiocarbamates via living polymerization.
- Activation of polythiocarbamates for substitution through oxidation.
- Broad functional group tolerance demonstrated under mild substitution conditions.
- Access to a diverse range of polyureas and polythiocarbamates achieved.
- Synthesis and functionalization of block copolymers using the developed strategy.
Conclusions:
- The developed method provides a versatile platform for postpolymerization modification of polythiocarbamates.
- This approach allows for the creation of diverse polymer structures, including polyureas and functionalized block copolymers.
- The strategy offers broad functional group tolerance and mild reaction conditions, making it attractive for precision nanomaterial synthesis.
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