Grid-corner analogues: Synthesis, characterisation and spectroscopic properties of meridional complexes of tridentate NNO Schiff-base ligands

Reactions of the tridentate Schiff-base ligands HL1, HL2 and HL3 formed from pyridine-2-aldehyde and 2-aminophenol plus two of its methoxycarbonyl derivatives, with AgNO3, [Cu(CH3CN)4]PF6, Cu(NO3)2, Co(NO3)2 and Zn(NO3)2 give complexes of the following types: [Ag(HL)2]NO3; (1a, 2a, 3a); [CuII(HL)L]PF6 (1b, 2b, 3b); [CuII(HL)L]NO3 (1c, 2c, 3c); and [M(HL)L]2[M(NO3)4] where MCo(II) (1d, 2d, 3d); or Zn(II) (1e, 2e, 3e), which in principle define the basic characteristics of the metal sites in certain metallogrids. The complexes have been characterized by spectroscopic techniques and elemental analysis. The solid state structures of complexes 2b and 2e have been established by X-ray crystallography.

Graphical abstractReactions of the tridentate Schiff-base ligands with metal ions possessing tetrahedral or octahedral coordination geometries give mononuclear complexes which in principle define the basic characteristics of the metal sites in certain metallogrids. The complexes have been characterized and investigated by various spectroscopic techniques, elemental analysis and X-ray crystallography.Figure optionsDownload full-size imageDownload as PowerPoint slide