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Cyclobutane dication, (CH₂)₄ ²⁺: a model for a two-electron four-center (2e-4c) Woodward-Hoffmann frozen transition state.

ABSTRACT: The structures of the elusive cyclobutane dication, (CH₂)₄ ²⁺, were investigated at the MP2/cc-pVTZ and CCSD(T)/cc-pVTZ levels. Calculations show that the two-electron four-center (2e-4c) bonded structure 1 involving four carbon atoms is a minimum. The structure contains formally two tetracoordinate and two pentacoordinate carbons. The non-classical ?-delocalized structure can be considered as a prototype for a 2e-4c Woodward-Hoffmann frozen transition state. The planar rectangular shaped structure 2 with a 2e-4c bond was found not to be a minimum.

SUBMITTER: Prakash GKS

PROVIDER: S-EPMC6633612 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Cyclobutane dication, (CH2)4 2+: a model for a two-electron four-center (2e-4c) Woodward-Hoffmann frozen transition state.

Prakash G K Surya GKS Rasul Golam G

Beilstein journal of organic chemistry 20190703

The structures of the elusive cyclobutane dication, (CH2)4 2+, were investigated at the MP2/cc-pVTZ and CCSD(T)/cc-pVTZ levels. Calculations show that the two-electron four-center (2e-4c) bonded structure 1 involving four carbon atoms is a minimum. The structure contains formally two tetracoordinate and two pentacoordinate carbons. The non-classical σ-delocalized structure can be considered as a prototype for a 2e-4c Woodward-Hoffmann frozen transition sta ...[more]

PMID: 31354864

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