Bonding in some Novel Organometallic Complexes of the First and Second Row Transition Metal Ions

Abstract

X-ray crystallographic analyses of a number of organometallic molecules have indicated that bonding of the cyclic ligands to transition metal ions differs considerably from that in such molecules as the bis π -cyclopentadienyl metal complexes. Thus in π-cyclopentadienyl-1-phenylcyclopentadiene — cobalt (1), cobalt (2, 3) tetrakis(trifluoromethyl) cyclopentadienone iron tricarbonyl (3), π-cyclopentadienyl hexakis(trifluoromethyl) benzenerhodium (4) and tricarbonyloctafluorocyclohexa-1, 3-diene iron (5), the essentially planar structure of the substituted diene, dienone or benzene ligand is considerably modified on bonding to the metal ion. The non-planarity of the ligand varies from some 20°in the case of the cyclopentadienone complex to approximately 47° in the benzene and hexa 1–3 diene structures.