Dbf-ruthenocenes: Towards chiral halfsandwich Lewis acidic Dbf complexes

摘要

In order to develop a new class of chiral metallocene catalysts, halfsandwich ruthenocenes of dibenzo[c,g]fluorenide (Dbf~(-1)) have been prepared. Structural and spectroscopic characterization of (η~5- Dbf)Ru(PPh_3)_2Cl and [(η~5-Dbf)Ru(PPh _3)_2(NCMe]~+[SbF_6]~- provide evidence for strong metal-ligand binding in these sterically crowded complexes. In the solid state the complexes assume conformations ideal for transfer of the stereo information unto a prochiral substrate.