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09:35
Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Benzyne cycloaddition onto carbon nanohorns.
Demetrios Chronopoulos1, Nikolaos Karousis, Toshinari Ichihashi
1Theoretical and Physical Chemistry Institute, National Hellenic Research Foundation, 48 Vassileos Constantinou Avenue, Athens 11635, Greece. tagmatar@eie.gr.
Nanoscale
|June 6, 2013
Summary
This study presents a new method for covalently modifying carbon nanohorns (CNHs) using benzyne chemistry. The functionalized CNHs were used to create novel hybrid materials for immobilizing gold nanoparticles.
Area of Science:
- Materials Science
- Nanotechnology
- Organic Chemistry
Background:
- Carbon nanohorns (CNHs) are novel carbon nanomaterials with unique structures.
- Covalent functionalization is crucial for tailoring CNH properties and applications.
- Developing facile and efficient functionalization methods for CNHs remains an active research area.
Purpose of the Study:
- To develop a facile covalent functionalization strategy for carbon nanohorns (CNHs).
- To explore the synthesis of novel CNH-based hybrid materials.
- To investigate the immobilization of gold nanoparticles onto functionalized CNHs.
Main Methods:
- In situ generation of benzynes from precursors like anthranilic acid or silyl triflates.
- Benzyne cycloaddition reaction for CNH functionalization under conventional and microwave conditions.
- Sonogashira coupling and condensation reactions to introduce specific functional groups.
- Characterization using spectroscopy, thermogravimetric analysis, electron microscopy, and light scattering.
Main Results:
- Successful covalent functionalization of CNHs via benzyne cycloaddition, creating fused ring structures.
- Synthesis of iodo-modified CNHs and subsequent extension with endocyclic disulfides.
- Immobilization of gold nanoparticles onto the functionalized CNHs, forming CNH-Au(nano) hybrid materials.
- Characterization confirming the structure and composition of the modified CNHs and hybrid materials.
Conclusions:
- The benzyne cycloaddition offers an efficient route for CNH covalent functionalization.
- The developed method enables the creation of advanced CNH-based hybrid materials.
- The CNH-Au(nano) hybrid material shows potential for various applications, particularly in catalysis and sensing.
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