Electrochemical synthesis of adducts of 2-aminopyridine or methanol in metal chelates of a N,N,N-tridentate Schiff base ligand.: X-ray crystal structures of the Ni(II) and Zn(II) derivatives

The electrochemical syntheses of series of novel adducts of 2-aminopyridine and methanol in Co(II), Ni(II), Cu(II) or Zn(II) chelates of the N,N,N-tridentate basic form of the Schiff base 2-N-tosylamino(2'-tosylaminobenzylidene)aniline (H2L), [M(L)L'] (M = Co, Ni, Zn, L' = 2-aminopyridine; M = Cu, L' = CH3OH), were performed by using the corresponding metal as a sacrificial anode. The compounds were characterized by elemental analysis, IR spectroscopy, FAB mass spectrometry, H-1 NMR and magnetic measurements. The crystal structures of the Zn and Ni derivatives as well as of the Schiff base have been determined by X-ray diffraction. In the 2-aminopyridine complexes this ligand is bound to the metal through the endocyclic nitrogen whereas the aminogroup is involved in intramolecular N-(HO)-O-... hydrogen bonds with one of the tosyl SO2 groups. (C) 2003 Elsevier Science Ltd. All rights reserved.