Synthesis and structural studies of some first row transition metal complexes of acetone isonicotinoyl hydrazone

Acetone isonicotinoyl hydrazone (AINH) has been found to form complexes of the types MCl₂·AINH·nEtOH and M(AINH-H)₂·nH₂O where M  Mn(II), Fe(II), Co(II), Ni(II), Cu(II) or Zn(II) and n  0, 1 or 2. Cu^ICl·AINH has also been prepared starting with Cu(II) chloride. All the complexes are found to be non-electrolytes in pyridine. Tentative structural conclusions are drawn for these complexes based upon electronic spectral and room-temperature magnetic measurements. IR spectral studies suggest that AINH functions as a bi- or tridentate ligand in the complexes of the former type and as a tridentate one in the latter type of complexes. The positions of the v(M-O) mode in the low frequency IR spectra of the complexes have been correlated with their overall stability constants, log K.