Template synthesis, structure and characterization of NiII2PbIIand CuII2PbIIcomplexes of macrocycles with a N4O2donor set

Abstract

The reaction of [N,N′-ethylene- or [N,N′-propane-1,3-diylbis(3-formyl-5-methylsalicylideneiminato)]-metal(II)(M = Cu or Ni) and a diamine (ethylenediamine, propane-1,3-diamine, butane-1,4-diamine or pentane-1,5-diamine) in the presence of lead(II) ion gives macrocyclic complexes [Pb(MLm,n)2]X2[H2Lm,n= macrocycle formed by the condensation of two molecules of 2,6-diformyl-4-methylphenol and two diamines H2N(CH2)mNH2 and H2N(CH2)nNH2; m= 2 or 3 and n= 2–5; M = Cu or Ni; X = CIO4, PF6, BPh4 or BF4]. They were characterized by elemental analyses, single-crystal X-ray analysis, fast atom bombardment mass, IR, electronic and ESR spectra and magnetic measurements. The crystal structure of [Pb(CuL3,3)2][CIO4]2 has revealed that the copper(II) ion in each CuL3,3 is bound at one of the N2O2 donor sites and the lead ion is sandwiched by the vacant N2O2 sites of two CuL3,3 entities, providing a square-antiprismatic environment.