Polynuclear and one-dimensional cyanide-bridged heterobimetallic complexes: synthesis, crystal structures and magnetic properties

Three new heterobimetallic cyanide-bridged complexes, {[Ni(L-1)][Ag(CN)(2)]}[Ag(CN)(2)] center dot 2H(2)O (2), {[Mn(L-2)][Ag(CN)(2)]} center dot 1.5H(2)O (3) and {[Mn(L-3)(H2O)](2)[Ag(CN)(2)]}ClO4 center dot 2H(2)O (4) (L-1=2,7,12-trimethyl-3,7,11,17-tetraazabicyclo[11.3.1] heptadeca-1(17), 13,15-triene; L-2 = N,N'-1,3-propylenebis(5-chlorosalicylideneiminate); L-3 = N,N'-1,2-propylene-bis(5-bromosalicylideneiminate)), have been assembled using for the first time a new polyaza macrocycle nickel(II) compound [Ni(L-1)](ClO4)(2)(1), or Schiff-base manganese(III) compounds and K[Ag(CN)(2)]. Single crystal X-ray diffraction analysis reveals that complexes 2 and 3 can be characterized as one-dimensional cationic and neutral single chain structure, respectively. Complex 3 forms a three-dimensional network via weak inter-chain Ag center dot center dot center dot Ag interactions. Complex 4 belongs to a cyanide-bridged bimetallic sandwich-like cationic trinuclear structure containing Mn2Ag core with free ClO4- as a counter anion, indicating that the Schiff-base ligand has an obvious influence on the structure of the cyanide-bridged complexes formed. Investigation of the magnetic susceptibilities of the cyanide-bridged AgNi(II)/Mn(III) complexes showed the weak anti-ferromagnetic interaction between neighboring paramagnetic Ni(II) or Mn(III) ions bridged by the long NC-Ag-CN unit. From the best-fit of the magnetic susceptibility data of complexes 2 and 4 the magnetic coupling constant was determined to be J = -0.51 and -0.78 cm(-1), respectively. Keywords.