Synthesis and solid-state molecular structures of nitrosoalkane complexes of iron porphyrins containing methanol, pyridine, and 1-methylimidazole ligands.
Nitrosoalkanes belong to the family of C-nitroso compounds and are known to bind to the iron center in heme proteins. We have prepared and characterized a series of new nitrosoalkane heme model complexes of the form (por)Fe(RNO)(L) (por=porphyrinato dianion; R=isopropyl; L=MeOH, pyridine, 1-methylimidazole) by infrared and 1H NMR spectroscopy and X-ray crystallography. Within the set of octaethylporphyrinato (OEP) compounds, the infrared stretching frequencies of the NO groups decrease in the order (OEP)Fe(iPrNO)(MeOH).MeOH (1433 cm-1) > (OEP)Fe(iPrNO)(py) (1429 cm-1) > (OEP)Fe(iPrNO)(1-MeIm) (1423 cm-1), reflecting the increased backdonation of electron density in the 1-methylimidazole derivative. The molecular structures of the compounds as determined by crystallography reveal N-binding of the nitrosoalkane ligands to the formally ferrous metal centers.
Sohl
Christal D
CD
Department of Chemistry and Biochemistry, University of Oklahoma, 620 Parrington Oval, Norman, OK 73019, USA.
Lee
Jonghyuk
J
Alguindigue
Susan S
SS
Khan
Masood A
MA
Richter-Addo
George B
GB
D006418:Heme / Q000138:chemical synthesis* / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry*; D008024:Ligands; D000432:Methanol / Q000737:chemistry*; D015394:Molecular Structure; D009603:Nitroso Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D011725:Pyridines / Q000737:chemistry*
D007093:Imidazoles; D008024:Ligands; D009603:Nitroso Compounds; D011725:Pyridines; D006418:Heme; C023666:pyridine; C018100:1-methylimidazole; D000432:Methanol