Synthetic strategy and structures of [Cr(CN)6]3-, [Mo(CN)8]3- and [W(CN)8]3- bridged di- and poly-nuclear transition metal-salen complexes: A review

The cyanide groups of [Cr(CN)(6)](3-), [Mo(CN)(8)](3-) and [W(CN)(8)](3-) may be used to bridge several mono-nuclear transition metal-salen complexes to form different di-, tri-, tetra- hexa- and poly-nuclear complexes of different molecular architectures. The synthetic strategy of the complexes generally involves the formation of H(2)salen type ligands by the 1:2 condensation of the appropriate diamine and salicylaldehyde derivatives in appropriate solvent at the beginning, followed by the formation of mononuclear transition metal-salen complexes, which are finally connected by [Cr(CN)(6)](3-), [Mo(CN)(8)](3-) and [W(CN)(8)](3-) bridges to form poly-nuclear complexes. In some cases, however, transition metal-salen units were not isolated, but they have been used in situ to synthesize cyanide bridged poly-nuclear complexes. The magnetic properties of these complexes are interesting. This review represents an overview on the synthetic strategies, structures, magnetic properties of these complexes. It is noteworthy that only those complexes are considered in this review whose X-ray structures are available.

Automated summary

This review provides an overview on the synthetic strategies, structures, and magnetic properties of transition metal-salen complexes bridged by cyanide groups. Only complexes with available X-ray structures are considered.