Variation of oxo-transfer reactivity of (nitro)cobalt picket fence porphyrin with oxygen-donating ligands.
Derivatives of (nitro)cobalt picket fence porphyrin with oxygen-donating ligands have been prepared in solution and in the solid state. Crystal structures of two of these derivatives, (H2O)CoTpivPP(NO2) and (CH3OH)CoTpivPP(NO2), have been determined. The ethanol complex (C2H5OH)Co(TPP)(NO2) has been obtained and spectrally characterized using sublimed layers methodology. The formation constant and the DeltaH degrees value of the association reaction with ethanol have been determined by FTIR measurements in CCl4 solution. Catalytic oxygen activation and oxo-transfer reactions of these derivatives have been assessed in solution. Correlations between the oxo-transfer reactivity, thermodynamics, and characteristics of the nitro ligand show that although calculated and observed ONO vibrational spectra and bond lengths suggest activation of the NO2 ligand and enhanced oxo-transfer reactions as seen in the analogous five-coordinate complexes, density functional theory calculations support that thermodynamics limits oxo-atom transfer reactions in these six-coordinate systems.
Goodwin
John
J
Department of Chemistry and Physics, Coastal Carolina University, P.O. Box 261954, Conway, South Carolina 29526-6054, USA. jgoodwin@coastal.edu
Kurtikyan
Tigran
T
Standard
Jean
J
Walsh
Rosa
R
Zheng
Bin
B
Parmley
Diedre
D
Howard
James
J
Green
Shaun
S
Mardyukov
Arthur
A
Przybyla
David E
DE