Complexes of nickel(II) perchlorate with polymethylenebis(phenylthiourea) ligands

Abstract

The behaviour of polymethylenebis(phenylthiourea) compounds as ligands (L) towards nickel(II) perchlorate has been investigated. The ligand PhHN·CS·NH·CH2·CH(Me)·NH·CS·NHPh, (I), gives a five-co-ordinate species of chromophore NiS4O; PhHN·CS·NH·[CH2]n·NH·CS·NHPh (III–X; n= 3–10) give insoluble complexes [NiL3(ClO4)2](n= 3–9) with octahedral stereochemistry and a soluble complex [NiL3(ClO4)2](n= 3) that dissociates in solution to give square-planar [NiL2]2+ species (where L is a bidentate ligand). An excess of L gives rise to formation of [NiL4]2+ species, still square planar in stereochemistry, in which the ligand is unidentate. The ligand (X; n= 10) also gives rise to square-planar [NiL4]2+ species in solution but excess of ligand tends to form [NiL6]2+ species having an octahedral NiS6chromophore.