Arene-chromium tricarbonyl complexes: bonding and behaviour

Publisher Summary This chapter discusses those complexes in which a transition metal is π-bonded to a six-membered aromatic hydrocarbon ring Recent X-ray structural investigations along with spectroscopic and theoretical studies have contributed significantly to the understanding of the bonding in arene metal complexes The cocondensation of transition-metal atoms and aromatic hydrocarbon at liquid nitrogen temperature leads directly to zero-valent arene complexes Reaction of disubstituted acetylenes with transition-metal compounds often leads to arene complexes The direct reaction between a metal carbonyl and an aromatic hydrocarbon often leads to the replacement of 2 or 3 carbonyl groups yielding arene complexes Monoarene complexes often undergo arene replacement reactions with ligands, such as arenas The parent compound bisbenzene chromium has been the subject of several structural analyses Molecular orbital calculations have been carried out on the arene tricarbonyl complexes of Cr, Mo, and W On the basis of overlap considerations, it has been suggested that the MO framework of the arene ring may play an important role in the metal–ligand bonding in arene chromium tricarbonyl complexes Vanadium hexacarbonyl reacts with various arenes yielding complexes [(arene)V(CO) 4 ] + [V(CO) 6 ] – from which hexafluorphosphate or tetraphenylborate salts can be prepared by metathesis reaction Bisarene chromium compounds have proven to be rather inert toward arene replacement by nonaromatic ligands The exchange of one arene ligand for another in arene tricarbonyl compounds has been of some synthetic value Phosphine and phosphite ligands react with arene tricarbonyl complexes

A. Mangini

Papers

P.M.R. spectra and solvent effect of some benzene-chromium-tricarbonyls