Heterometallic Compounds Assembled from Ferrocene-Containing Bisthiosemicarbazone Clips

Heteropolynuclear organometallic compounds have been constructed by using the ferrocene-based ligand H2L, [NH2SCNHN=C(CH3)(C5H4)]2Fe. Reaction of the ligand H2L with the cobalt(II) salt gave a tetranuclear helicate Co2Fe2 (1) with two ferrocene-based clips wrapped around the two cobalt atoms. The chiral helicates recognized the neighbors with same chirality through intermolecular hydrogen bonding between the thiosemicarbazone moieties to form a one-dimensional chiral channel. Reaction of the ligand H2L with the cadmium(II) salt afforded a tetranuclear dimeric compound Cd2Fe2 (2), with two symmetric related parts bridged through two sulfur atoms. Reaction of the ligand H2L with the copper(I) salt, in the presence of triethylamine, resulted in a hexanuclear compound Cu4Fe2 (3) with a crownlike Cu4S4 octagon similar to that of S8 sited inside and two ferrocene-containing ligands positioned outside. Electrochemical measurements were displayed to investigate the redox communications between the ferrocene moieties through metal centers.