Coupling constants in fluorinated cyclic compounds. Part 2.—Fluorocyclopentenes and perfluorocyclohexadiene-1,3

Abstract

Fluorine-fluorine coupling constants have been determined in perfluorocyclohexadiene-1,3 and in a series of halogenated cyclopentenes. Analysis of the spectra of these compounds shows them to be deceptively simple due to the equality of certain vicinal cis and trans F—F couplings. The magnitudes and relative signs of these parameters have been obtained. The coupling across a double bond has a surprisingly small value.