METAL-MEDIATED SYNTHESIS OF MULTIDOMAIN LIGANDS - A NEW STRATEGY FOR METALLOSUPRAMOLECULAR CHEMISTRY

The bridging ligand bis{4'-(2,2':6',2 ''-terpyridinyl)}ether (1) can be prepared in 69% yield from the reaction of 4'-chloro-2,2':6',2 ''-terpyridine (3) with 2,2':6',2 ''-terypridin-4'(1'H)-one (2) in Me(2)NCHO in the presence of KOH. More conveniently, complexes of 1 can be prepared in situ by the reaction of 2 with a ruthenium(II) complex of 3 in the presence of K2CO3. This methodology has been developed for the synthesis of a range of mono-, di-, tri- and hexanuclear complexes with a variety of Xtpy (Xtpy = 4'-substituted 2,2':6',2 ''-terpyridine) terminator ligands. The molecular structure of 1 (a = 9.623(2), b = 11.241(1), c = 11.828(1) Angstrom; space group P ($) over bar 1: alpha = 93.064(9), beta = 107.072(14), gamma = 99.088(14)degrees; Z = 2, R = 0.0450, R(w) = 0.0577) has been determined. The generality of the methodology may ultimately be limited by the sensitivity of the ether-linkage in 1 to attack by nucleophiles.