84433-40-9Relevant academic research and scientific papers
Metal-nitroxyl interactions. 27. Comparison of electron-electron spin-spin coupling constants for urea and amide linkages in spin-labeled copper porphyrins
More, Kundalika M.,Eaton, Gareth R.,Eaton, Sandra S.
, p. 934 - 939 (2008/10/08)
A series of spin-labeled copper porphyrins has been prepared with urea linkages between the porphyrin ring and the nitroxyl ring. The electron-electron coupling constants, J, have been obtained from the solution EPR spectra. The observed values of J are lower by factors of about 2 to >40 for the compounds with urea linkages than for analogous compounds with amide linkages. The decreased values of J for the urea linkages are consistent with a largely σ-bonding pathway for the copper-nitroxyl interaction. In several cases two components were observed in the EPR spectra. These are attributed to different conformations of the porphyrin-nitroxyl linkage.
