The reaction of 2-tosylaminobenaldehide or 1-phenyl-3-methyl-4-formyl-5- pyrazolone with 2-(hydroxymethyl)aniline results in the formation of novel tridentate N,N,O or N,O,O ligand systems I, II respectively, which react with copper, nickel or cobalt acetates to furnish the binuclear complexes of Cu(II) III, IV and mononuclear coordination compounds for Ni(II) and Co(II) V.fgiureFormulation of all compounds is based upon satisfactory C, H, N elemental analyses, IR and 1H NMR and EXAFS spectroscopies. The magnetochemical measurements in the range 294- 77.4 K confirm the binuclear structures for III and IV with a strong antiferromagnetic exchange (for III, -2J = - 630 cm-1; complex IV is diamagnetic at room temperature) while the values of magnetic moments µeff for V (M = Ni, Co) 3.17 and 4.70 B.M. correspondingly favor the mononuclear structure for both coordination compounds. The X-ray data for IV (L = II, M = Cu) (fig. 1) and V (L = II, M = Ni) (fig. 2) unambiguously confirm the structure of complexes III, IV and V.figureFig 1 Molecular structure of IVFig. 2 Molecular structure of V (M = Ni)