Syntheses and reactions of bromotetrafluorophenyl(cyclopentadienyl)dicarbonyliron derivatives

Abstract

The isomeric bromotetrafluorophenyl(cyclopentadienyl)dicarbonyliron compounds have been prepared by both the nucleophilic displacement of bromide ion from dibromotetrafluorobenzene by the (cyclopentadienyl)dicarbonyliron anion, in the form of its lithium salt, and by reaction between the corresponding lithiobromotetrafluorobenzene and (cyclopentadienyl)dicarbonyliron iodide. The resultant bromotetrafluorophenyliron derivatives undergo lithium–bromine exchange in preference to carbon–iron bond cleavage, to give the corresponding lithiotetrafluorophenyliron derivative. Reaction of the m- and p-isomers of the above with (cyclopentadienyl)dicarbonyliron iodide gave the 1,3- and 1,4- bis-[(cyclopentadienyl)dicarbonyliron]tetrafluorobenzenes.