Synthesis, structural and spectroscopic characterization of four [(η6-PAH)Cr(CO)3] complexes (PAH = pyrene, perylene, chrysene, 1,2-benzanthracene)

The thermal reaction of hexacarbonylchromium with the polycyclic aromatic hydrocarbons (PAHs) pyrene, perylene, chrysene and 1,2-benzanthracene has afforded four organometallic complexes of the type [(eta(6)-PAH)Cr(CO)(3)], whose unprecedented structures were obtained by single-crystal X-ray analysis. The topology of the coordination of the Cr(CO)3 fragment and its asymmetry with respect to the coordinating ring may depend on the opportunity to maintain the maximum aromaticity of the complexed ligand. DFT calculations, H-1 NMR, FT-IR and Raman spectroscopy have been used to elucidate the type of interaction between the PAH ligand and the carbonylmetal moiety, giving insight into the ligand-tometal donor capacity and the intra- and intermolecular interactions. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).