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Updated: Oct 3, 2025

Free Radicals in Chemical Biology: from Chemical Behavior to Biomarker Development
Published on: April 15, 2013
Synthesis, properties and chemical modification of a persistent triisopropylsilylethynyl substituted
Tomohiko Nishiuchi1,2, Daisuke Ishii1, Seito Aibara1
1Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan. nishiuchit13@chem.sci.osaka-u.ac.jp.
Abstract:
In studies aimed at developing new organic spin materials, we prepared a triisopropylsilylethynyl substituted tri(9-anthryl)methyl (TAntM) radical. The TIPS-ethynyl group in this radical effectively suppresses its reactivity, resulting in extremely high stability in air for at least one month. Chemical modification of the radical using [4+2] Diels-Alder reaction proceeds even at room temperature. Because harsh conditions and metal-catalyzed reactions are not required, this post-modification strategy should be highly versatile for use in constructing unique spin-labelled molecules.
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