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Updated: Jul 12, 2026
10:44
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Radical reactions of c60
Science (New York, N.Y.)
|November 22, 1991
Summary
Benzyl and methyl radicals readily add to C(60) fullerenes. Stable radical adducts, identified by ESR spectroscopy, show localized unpaired electrons protected by substituents.
Area of Science:
- Fullerenes Chemistry
- Radical Chemistry
- Photochemistry
Background:
- Fullerenes, particularly C(60), are carbon allotropes with unique electronic properties.
- Radical addition reactions are crucial for functionalizing fullerenes.
- Photochemical methods offer controlled generation of reactive species.
Purpose of the Study:
- To investigate the photochemical addition of benzyl and methyl radicals to C(60) fullerenes.
- To characterize the resulting radical and nonradical adducts.
- To understand the stability and electronic properties of these adducts.
Main Methods:
- Photochemical generation of benzyl and methyl radicals.
- Reaction of radicals with C(60).
- Characterization using Electron Spin Resonance (ESR) spectroscopy and Mass Spectrometry.
Main Results:
- Formation of benzyl radical adducts (RnC(60)) with n=1 to at least 15.
- Identification of stable allylic (n=3) and cyclopentadienyl (n=5) benzyl radical adducts via ESR.
- Formation of methyl radical adducts ((CH3)nC(60)) with n=1 to at least 34, analyzed by mass spectrometry.
Conclusions:
- Benzyl and methyl radicals add efficiently to C(60) under photochemical conditions.
- Steric protection by benzyl groups contributes to the stability of radical adducts.
- The unpaired electron in stable adducts is localized on the C(60) surface.
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