The azidopentacyanoferrate(III) ion as a tecton in constructing heterometallic complexes: Synthesis, crystal structure and magnetic properties of [Mn(valphen)(H2O)2]2[(H2O)(valphen)Mn(μ-CN)Fe(CN)4(N3)]·8H2O

By employing the common precursor Na3[Fe(CN)5(NH3)]·3H2O in a new synthetic approach, the azidopentacyanoferrate(III) ion has been isolated and structurally characterized as (Ph4As)2[Na(H2O)4][Fe(CN)5(N3)] 1. In order to confirm its building block ability, compound 1 has been reacted with the mononuclear complex [Mn(valphen)(H2O)2]ClO4 (H2valphen represents the Schiff base resulting from the condensation of o-vanillin with 1,2-phenylenediamine in a 2:1 M ratio) to afford the new MnIII–FeIII heterometallic system [Mn(valphen)(H2O)2]2[(H2O)(valphen)Mn(μ-CN)Fe(CN)4(N3)]·8H2O 2. The crystal structure of compound 2 reveals a supramolecular assembly generated by [(H2O)(valphen)Mn(μ-CN)Fe(CN)4(N3)]2− dianions and discrete [Mn(valphen)(H2O)2]+ counterions. The dynamic magnetic measurements of compound 2 point to a slow relaxation of the magnetization.