Metal complexes of tetradentate and pentadentate N- o-hydroxybenzamido- meso-tetraphenylporphyrin ligand: M( N-NCO( o-OH)C 6H 4-tpp) (M = Zn 2+, Ni 2+, Cu 2+) and M′( N-NCO( o-O) C 6H 4-tpp) (M′ = Mn 3+) (tpp = 5, 10, 15, 20-tetraphenylporphyrinate)

Abstract

The crystal structures of N- o-hydroxybenzimido- meso-tetraphenylporphyrinatozinc(II) toluene solvate [Zn( N-NCO( o-OH)C 6H 4-tpp)·C 6H 5CH 3; 4·C 6H 5CH 3], N- o-hydroxybenzimido- meso-tetraphenylporphyrinatonickel(II) chloroform solvate [Ni( N-NCO( o-OH)C 6H 4-tpp)·0.6CHCl 3; 5·0.6 CHCl 3], N- o-hydroxybenzimido- meso-tetraphenylporphyrinatocopper(II) toluene solvate [Cu( N-NCO( o-OH)C 6H 4-tpp)·C 6H 5CH 3; 6·C 6H 5CH 3] and N- o-oxido-benzimido- meso-tetraphenylporphyrinato(-κ 4,N 1,N 2,N 3,N 5,κO 2) manganese (III) methylene chloride·methanol solvate [Mn(N-NCO( o-O)C 6H 4-tpp)·CH 2Cl 2·MeOH; 8·CH 2Cl 2·MeOH] were established. The coordination sphere around Zn 2+ ion in 4·C 6H 5CH 3, (or Ni 2+ ion in 5·0.6 CHCl 3 or Cu 2+ ion in 6·C 6H 5CH 3) is a distorted square planar (DSP) whereas for Mn 3+ in 8·CH 2Cl 2·MeOH, it is a distorted trigonal bipyramid (DTBP) with O(1), N(1) and N(3) lying in the equatorial plane for 8·CH 2Cl 2·MeOH. The g value of 8.27 measured from the parallel polarization of X-band EPR spectra at 293 K is consistent with the high-spin mononuclear manganese(III) (S = 2) in 8. The magnitude of axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) in 8 was determined approximately as 3.0 cm −1 by the paramagnetic susceptibility measurements and conventional EPR spectroscopy.