ENANTIOMERICALLY PURE CHIRAL RU-II(L-BOOLEAN-AND-L)(2) BUILDING-BLOCKS FOR COORDINATION-COMPOUNDS

The synthesis of dinuclear complexes, where each metal center has a tr is-bidentate coordination sphere, with defined stereochemistry is repo rted. Using Delta- and Lambda-[Ru(L Lambda L)(2)(py)(2)](2+) (L Lambda L = 2,2'-bipyridine and 1,10-phenanthroline) as enantiomerically pure chiral building blocks, the three possible isomers (Delta Delta, Lamb da Lambda, and Delta Delta) of [Ru(phen)(2)-bpym-Ru(phen)(2)](4+) and two diastereoisomers (Delta Delta and Delta Lambda) of the dinuclear c omplex [Ru(bpy)(2)4,6-dppm-Ru(bpy)(2)](4+) were characterized by means of CD and NMR spectroscopy (bpym = 2,2'-bipyrimidine, 4,6-dppm = 4,6- di-2-pyridylpyrimidine). A study of substitution of the two pyridine l igands with (R,R)-1,2-diaminocyclohexane (R,R-dach) was carried out wi th the same enantiomerically pure chiral building blocks. It was found that substitution occurs under retention of configuration.