Transmission mechanisms of four-bond 19F19F coupling constants in fluoropropenes: A theoritical and experimental study

Four-bond FF couplings were measured in cis- and trans-isomers of 1,3-diflouro- and 1,3,3,3-tetraflouro-propene. These couplings show a pronounced depedence on the member of flourines attached to the sp3 carbon atom. This dependence is much larger for the cis-isomers than for the trans ones. A theor...

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Autores principales: Natiello, M.A., Contreras, R.H., Gavarini, H.O., Rae, I.D.
Formato: JOUR
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_03010104_v98_n2_p279_Natiello
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Sumario:Four-bond FF couplings were measured in cis- and trans-isomers of 1,3-diflouro- and 1,3,3,3-tetraflouro-propene. These couplings show a pronounced depedence on the member of flourines attached to the sp3 carbon atom. This dependence is much larger for the cis-isomers than for the trans ones. A theoretical analysis of transmission mechanisms of the Fermi contact, orbital and dipolar interacting terms is carried out using inner projections of the polarization propagator at the INDO level of approximation. For each interacting term three different coupling pathways are considered, namely, through-space, σ- and π-electron contributions. Trends for each mechanism are discussed and results are compared with the experimental values. © 1985.