The azidopentacyanoferrate(III) ion as a tecton in constructing heterometallic complexes: Synthesis, crystal structure and magnetic properties of [Mn(valphen)(H_2O)_2]_2[(H_2O) (valphen)Mn(μ-CN)Fe(CN)_4(N_3)]·8H_2O

摘要

By employing the common precursor Na_3[Fe(CN)_5(NH _3)]·3H_2O in a new synthetic approach, the azidopentacyanoferrate(III) ion has been isolated and structurally characterized as (Ph_4As)_2[Na(H_2O)_4][Fe(CN) _5(N_3)] 1. In order to confirm its building block ability, compound 1 has been reacted with the mononuclear complex [Mn(valphen)(H _2O)_2]ClO_4 (H_2valphen 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 Mn~(III)- Fe~(III) heterometallic system [Mn(valphen)(H_2O) _2]_2[(H_2O)(valphen)Mn(μ-CN)Fe(CN) _4(N_3)]·8H_2O 2. The crystal structure of compound 2 reveals a supramolecular assembly generated by [(H _2O)(valphen)Mn(μ-CN)Fe(CN)_4(N_3)] ~(2-) dianions and discrete [Mn(valphen)(H_2O) _2]~+ counterions. The dynamic magnetic measurements of compound 2 point to a slow relaxation of the magnetization.