SYNTHESIS, CHARACTERIZATION, AND STRUCTURAL INVESTIGATION OF NEW ETA(5)-CYCLOPENTADIENYLBIS-8-HYDROXYQUINOLINATOMETAL(IV) COMPLEXES

By the interaction of M(eta(5)-C(5)H(4)R)(2)Cl-2 (M = Zr, Hf; R=H, Me, SiMe(3)) and 8-hydroxyquinoline (oxH) or 5-chloro-8-hydroxyquinoline (ox'H) in dichloromethane solution at 20 degrees C, the compounds M(eta(5)-C(5)H(4)R)Clox(2) and M(eta(5)-C(5)H(4)R)Clox(2)' were prepared respectively. A similar reaction of Ti(eta(5)-C5H5)Cl-3 with ox'H in acetonitrile solution gave Ti(eta(5)-C5H5)Clox(2)'. All complexes were characterized by elemental microanalysis and by IR and H-1 NMR spectroscopy. X-ray analysis of M(eta(5)-C(5)H(5)R)Clox(2)' (M = Ti, Hf) shows that these molecules may be described in terms of stereochemistry of eight-coordination approximating dodecahedral geometry more closely than octahedral geometry. With respect to octahedral coordination, the nitrogen atoms lie in a cis-configuration and the oxygen atoms in a trans-configuration Dichloromethane molecules co-crystallize with the hafnium complex and occupy a position on the 2-fold axis. The structural results are compared with those in related compounds.