二甲胺基尾式卟啉铁在 NO,CO,O_2及吡啶、二乙胺存在下的电化学行为

Influence of NO,CO,O_2,Pyridine,Et_2NH on the Redox Reaction of a New Tailed Iron Porphyrin

用电化学方法测定了氯化5-邻-(4-二甲胺基丁酰胺)苯基-10,15,20-三苯基卟啉合铁(Ⅲ)(简作 meso-MDMBPTPPFe(Ⅲ)Cl)在非配位溶剂1,2-二氯乙烷中,有 NO,CO,O_2,吡啶、二乙胺存在时的半波电位 E_(1/2),讨论了其氧化还原过程.

The electrochemistry of a tailed porphyrin iron,meso-mono[0-(4-dimethy- laminobutylamido) phenyl]triphenylporphyrin iron,was investigated in the presence of NO,CO,O_2 ,Py ,Et_2NH in nonaqueous media.The The E_(1/2) value of Fe (Ⅲ)/Fe(Ⅱ)shifts an- odically by 70 mV comparing to TPPFe and E_(1/2) value of Fe(Ⅱ)/Fe(Ⅰ) shifts cathodi- cally by 40 mV.This can be considered as the result of binding of the Me_2N—of the tail with iron(Ⅱ) but not iron(Ⅲ).In the presence of CO,the E_(1/2) value of Fe(Ⅲ)/Fe (Ⅱ)shifts anodically by 810 mV and the E_(1/2) of Fe(Ⅱ)/Fe(Ⅰ)shifts cathodically by 150 mY.The Fe(Ⅲ)/Fe(Ⅱ) potential for PFe(NO) is the most positive ever measured for a five -coordinate iron porphyrin and indicates extreme stability of Fe (Ⅱ) oxidation. The reduction was irreversible and suggested the electrode reaction involving an EC mecha- nism.The E_(1/2) of PFe(Ⅱ)Py,Fe(Ⅱ)/Fe(Ⅰ),shifts cathodically by 170 mV.In the presence of Et_2NH,the reduction was irreversible.