η 6 -Fluorene and η 5 -fluorenyl complexes of iron and manganese; X-ray structure of (η 5 -cyclopentadienyl)(η 6 -fluorenyl)iron

Reversible deprotonation of [Fe(C5H5)(η6-fluorene)]PF6 and [Mn(η6-fluorene)(CO)3]PF6 initially produces zwitterionic complexes wherein co-ordination to the six-membered ring is retained, and the manganese complex very slowly reverts to the isomeric η5 complex, [Mn(η5-fluorenyl)(CO)3]; the X-ray structure of the iron compound [Fe(C5H5)(C13H9)] has been determined.