THE DOUBLE-HELICAL BINUCLEAR COPPER COMPLEX OF 6,6''''-DIMETHYL-4',4'''-DIPHENYL-QUINQUEPYRIDINE AND MONOHELICAL CADMIUM COMPLEX OF 6,6''''-DIMETHYL-QUINQUEPYRIDINE - SYNTHESES, CRYSTAL AND MOLECULAR-STRUCTUREOF [CU-2(L(2))(2)][CLO4](3)CENTER-DOT-2CH(3)CN AND [CDL(1)][CLO4](2)

The binuclear copper complex of 6,6''''-dimethyl-4',4'''-diphenylquinq uepyridine L(2) and the mononuclear cadmium complex of 6,6''''-dimethy l-quinquepyridine L(1) have been prepared by the reaction of L(2) with Cu(ClO4)(2) . 6H(2)O and L(1) with Cd(ClO4)(2) . 2H(2)O, respectively . These complexes were characterized by elemental analysis, IR, H-1 NM R and fast atom bombardment MS spectra. X-ray crystallographic measure ment reveals that a Cu-I Cu-II mixed valence state copper complex is o btained, in which two ligand molecules self-organized around the Cu-I and Cu-II ions to form a double helical configuration. The cadmium com plex is mononuclear, has a highly symmetrical configuration and may be regarded as a monohelical compound. (C) 1997 Elsevier Science Ltd.