A forbidden rearrangement
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Updated: Jul 25, 2026

Plasmid-derived DNA Strand Displacement Gates for Implementing Chemical Reaction Networks
Published on: November 25, 2015
Martin Leivers1, Iris Tam, Kevin Groves
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Abstract:
[reaction: see text] A barrelene derivative fragments to afford benzene and trappable 1,2,3-tricyanocyclopropene. The barrelene anion fragments more easily to liberate benzene and the 1,2,3-tricyanocyclopropenyl anion, which is not trappable or stable in solution. However, the major thermal product from the barrelene anion is a rearranged allyl anion that is formed by disrotatory cleavage of the cyclopropyl ring, a formally Woodward-Hoffmann-forbidden process. Several proposals are offered to rationalize this forbidden rearrangement.
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