STEREOSELECTIVE SYNTHESIS OF OCTAHEDRAL COMPLEXES WITH PREDETERMINED HELICAL CHIRALITY

Facile stereoselective synthesis of an enantiomerically pure DELTA-Ru- trisbipyridine type complex is accomplished by using a new chiral and conformationally rigid ligand, which completely predetermines the heli cal chirality of the metal, yielding exclusively DELTA-configuration i n the present case. The ligand, abbreviated chiragen[6] is a bisbipyri dine compound, where two pinene substituted bipyridine units are linke d through an aliphatic C6-chain. The two remaining coordination sites of the complex are occupied by 4,4'-dimethylbipyridine. The structure of the u(chiragen-[6])(4,4'-dimethylbipyridine)](CF3SO3)2 complex has been determined by X-ray crystallography. Metal complexes formed by ch iragen ligands have potential applications in enantioselective catalys is and as chiral building blocks for polynuclear species.