STEREOCHEMICAL CONTROL OF DONOR AND ACCEPTOR GROUPS IN A MONOMERIC CHROMOPHORE-QUENCHER COMPLEX OF RUTHENIUM(II)

The chromophore-quencher complex [Ru(Me(2)bpy)(bpy-MV2+)(bpy-PTZ)](4+) , containing one donor (phenothiazine, PTZ) and one acceptor (methyl v iologen, MV2+) functionality, has been synthesized and separated into its four geometric isomers. This was achieved through the intermediacy of [Ru(Me(2)bpy)(bpy-MV2+)(py)(2)](4+), the two isomers of which were separated and each reacted stereoselectively with bpy-PTZ to produce two distinct isomer pairs of the target molecule, Cation-exchange chro matography allowed separation to realize the four forms. The isomers o f the product and of the intermediates were characterized by NMR spect roscopy. This is the first example of the isolation of geometric isome rs of a mononuclear system containing a single donor and single accept or functionality.