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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Electronic nature of carbonium ions and their silicon analogues
Caio L Firme1, O A C Antunes, Pierre M Esteves
1Universidade Federal do Rio de Janeiro, Instituto de Química, Avenida Athos da Silveira Ramos, 149, CT Bloco A, Sala 622, Cidade UniversitAria, Ilha do Fundão, Rio de Janeiro, BR 21941-909, Brazil. cfirme@iq.ufrj.br
Abstract:
Nonclassical ions or carbonium ions have multi-center bonding from delocalized sigma or pi electrons. The 2-norbornyl cation, its derivative 6,6-difluoro-2-norbornyl cation, tris-homocyclopropenyl cation, 7-norbornenyl cation, and 4-cyclopentenyl cation and their corresponding silicon analogues were studied in this work. All carbocations have topologically different 3c-2e systems. The magnitude of all delocalization indexes between each atomic pair of the 3c-2e bond can be used to predict homoaromaticity. The silicon analogues have a topologically different 3c-2e bond from their corresponding carbocation.
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