2,2 ': 6 ',2 ''-Terpyridine-4 '(1 ' H)-thione: a missing link in metallosupramolecular chemistry

The compound 2,2': 6',2 ''-terpyridine-4'(1'H)-thione 1 has been prepared and structurally characterised; in both the solid state and in solution, the thione tautomer is dominant. Compound 1 is a key entry into 4'-sulfur-functionalised tpy ligands and a representative alkylation with an electrophilic Frechet dendrimer is presented and the structural characterisation of the new ligand 4 reported. Oxidation of 1 yields bis(2,2': 6',2 ''-terpyridin- 4'-yl) disulfide 2 which is a novel homoditopic tpy ligand and which forms a tetranuclear [ 4 + 4] iron (II) metallomacrocycle. Structural characterisation of 2 and preliminary data for the iron complex are presented.