56961-38-7Relevant academic research and scientific papers
Dependence of 13C NMR Chemical Shifts in Arylcyclopropanes on Conformation and Electron Demand
Jason, Mark E.,Kurzweil, Peter R.,Leonard, Karen E.
, p. 2550 - 2555 (2007/10/02)
The 13C NMR spectra of conformationally rigid arylcyclopropanes have been examined in order to determine the strength and conformational dependence of the benzene-cyclopropane interaction.Previous work with conformationally flexible arylcyclopropanes has implicated both conjugative and hyperconjugative interactions between the aromatic ?-system and the bonding orbitals of cyclopropane.The substituent-induced chemical shifts are inconsistent with either mechanism being dominant.Replacement of the two hydrogen atoms on a cyclopropane methylene carbon with chlorine causes a reversal of the normal SCS response imposed by substitution on the aromatic ring.The model systems used were spiro-fluorene>, 1,1-diphenylcyclopropane, and 1,1a,6,6a-tetrahydrocyclopropindene.
