Intermediate (S = 1) spin state in five-coordinate cobalt(III): magnetic properties of N-o-hydroxy-benzamido-meso-tetraphenylporphyrin cobalt(III), Co(N-NCO(o-O)C6H4-tpp).
The crystal structures of paramagnetic N-o-oxido-benzimido-meso-tetraphenylporphyrinato (-kappa(4),N(1),N(2),N(3),N(5),kappaO(2))cobalt(III) [Co(N-NCO(o-O)C(6)H(4)-tpp); 2] (S = 1) and diamagnetic N-o-oxido-benzimido-meso-tetraphenylporphyrinato (-kappa(4),N(1),N(2),N(3),N(5),kappaO(2)) gallium(III) chloroform.methanol solvate [Ga(N-NCO(o-O)C(6)H(4)-tpp).0.5CHCl(3).MeOH; 3.0.5CHCl(3).MeOH] (S = 0) were determined. The coordination sphere around Co(III) in 2 [or Ga(III) in 3.0.5CHCl(3).MeOH] is described as five-coordinate distorted trigonal bipyramid (DTBP) with O(1), N(1) and N(3) [or O(2), N(1), N(3)] lying in the equatorial plane for 2 [or 3.0.5CHCl(3).MeOH]. The magnitude of axial (D) zero-field splitting (ZFS) for the Co(III) (S = 1) in 2 was determined as approximately 107 cm(-1) by paramagnetic susceptibility measurements. The compound (2) reacts in donor solvent such as pyridine to form six-coordinate diamagnetic species of the type Co(N-NCO(o-O)C(6)H(4)-tpp)(py) (4), whose (1)H NMR spectra can be interpreted as for Co(III) in an octahedral environment.
Cho
Cheng-Hsiung
CH
Department of Chemistry, National Chung Hsing University, Taichung, 40227, Taiwan.
Chien
Ting-Yuan
TY
Chen
Jyh-Horung
JH
Wang
Shin-Shin
SS
Tung
Jo-Yu
JY
D003035:Cobalt / Q000737:chemistry*; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D008665:Metalloporphyrins / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*
D008665:Metalloporphyrins; D009942:Organometallic Compounds; D003035:Cobalt