Cyanide-bridged polynuclear heterobimetallic complexes: synthesis, crystal structures, and magnetic properties

The reactions of [Mn III (3-EtOSalen)(H 2 O) 2 ]ClO 4 (Salen= N , N -ethylenebis(salicylideneaminato)dianion) with K 3 [M(CN) 8 ] (M=Mo, W) have been investigated, from which cyanide-bridged hexanuclear Mo–Mn and binuclear W–Mn complexes formulated as {[Mn(3-EtOSalen)(H 2 O)] 4 [Mn(3-EtOSalen)(CH 3 OH)][MoCN 8 ]}(CN) 2 ·CH 3 CN·H 2 O ( 1 ) and {[Mn(3-EtOSalen)(H 2 O) 2 ][Mn(3-EtOSalen)(H 2 O)(EtOH][Mn III (3-EtOSalen)(H 2 O) W(CN) 8 ]}·0.5CH 3 OH ( 2 ), respectively, were obtained and characterized by elemental analysis, IR spectroscopy and X-ray crystal structure determination. X-ray diffraction analysis for complex 1 shows that it has a cyanide-bridged cationic hexanuclear Mn 5 Mo structure in which two free and disordered CN − ions from the cyanide precursor are present as balance anions, while the [Mo(CN) 8 ] 3− ion acting as a pentadentate ligand connects five Schiff base manganese(III) units. In complex 2 , the [W(CN) 8 ] 3− ion is coordinated with a single Schiff base manganese unit by one of its cyanide groups, so forming a cyanide-bridged anionic binuclear structure whose dinegative charge is balanced by two free Schiff base manganese cations. Both of these cyanide-bridged complexes can be considered as self-complementary, such that the coordinated aqua ligand from one complex and the O 4 compartment from the Schiff base ligand of the neighboring complex form a supramolecular two-dimensional network and a one-dimensional ladder-like double-chain structure, respectively. Investigation of the magnetic properties of these complexes reveals antiferromagnetic interactions within the cyanide-bridged Mn–Mo/W units. The magnetic susceptibilities of both complexes have been modeled.