Copolymerization of Fe4Cu2C(CO)12 moieties with bidentate N-ligands: synthesis and crystal structure of the [Fe4Cu2(micro6-C)(CO)12(micro-bipy)]4.8THF square tetramer and the infinite [Fe4Cu2(micro6-C)(CO)12(micro-L-L)]infinity zigzag chains.

Substitution of the acetonitrile ligands in Fe(4)Cu(2)C(CO)(12)(MeCN)(2) with bidentate L-L ligands, such as 4,4'-bipyridine (bipy), pyrazine (pyz) or p-dicyanobenzene (p-DCB), gives rise to either infinite [Fe(4)Cu(2)(micro(6)-C)(CO)(12)(micro-L-L)](infinity) zigzag chain polymers or to [Fe(4)Cu(2)(micro(6)-C)(CO)(12)(micro-L-L)](4).8THF square oligomers, as a function of the crystallization solvent.