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Reactivity of a σ,σ,σ,σ-tetraradical: the 2,4,6-tridehydropyridine radical cation
Vanessa A Gallardo1, Bartłomiej J Jankiewicz, Nelson R Vinueza
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
Abstract:
The 2,4,6-tridehydropyridine radical cation, an analogue of the elusive 1,2,3,5-tetradehydrobenzene, was generated in the gas phase and its reactivity examined. Surprisingly, the tetraradical was found not to undergo radical reactions. This behavior is rationalized by resonance structures hindering fast radical reactions. This makes the cation highly electrophilic, and it rapidly reacts with many nucleophiles by quenching the N-C ortho-benzyne moiety, thereby generating a relatively unreactive meta-benzyne analogue.
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