Knotted Heterodinuclear Complexes

Surprisingly stable is the dinuclear complex cation [1CuCu]2+ with entwined ligand 1 (shown on the right; •, ○ = Cu+) that can be demetalated in a stepwise manner. The singly demetalated complex [1Cu]+ can be converted to give dissymmetrical heterodi-nuclear complexes [1CuAg]2+ and [1CuZn]3+ (○ = Ag+ and Zn2+, respectively). The electrochemical and spectroscopic properties of these molecular knots, in which the coordinating phenanthroline groups are linked through a “conducting” phenylene spacer, differ considerably from the corresponding compounds with “nonconducting” bridges.