Substituent Effects on Nitrosyl Iron Corrole Complexes Fe(Ar3C)(NO)
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- 作者：Crisjoe A. Joseph ; Matthew S. Lee ; Alexei V. Iretskii ; Guang Wu ; and Peter C. Ford
- 刊名：Inorganic Chemistry
- 出版年：2006
- 出版时间：March 6, 2006
- 年：2006
- 卷：45
- 期：5
- 页码：2075 - 2082
- 全文大小：232K
- 年卷期：v.45,no.5(March 6, 2006)
- ISSN：1520-510X
文摘
A series of nitrosyl tris(5,10,15-aryl)corrolate complexes of iron(III) Fe(Ar3C)(NO) with different substituents on thearyl groups have been prepared, and certain spectroscopic and reaction properties were compared. The cyclicvoltammetric analysis of the various Fe(Ar3C)(NO) complexes demonstrated that both the one-electron oxidationand one-electron reduction potentials respond in systematic and nearly identical trends relative to the electron-donor properties of the substituents. A similar pattern was seen in the nitrosyl stretching frequency, 
NO, whichmodestly decreased with the stronger donor substituents. Flash photolysis of Fe(Ar3C)(NO) solutions in tolueneleads to NO dissociation followed by rapid [NO]-dependent decay of the transients formed (presumably Fe(Ar3C))to regenerate the original spectra. As was seen in an earlier flash photolysis study of Fe(TNPC)(NO) (TNPC3- =5,10,15-tris(4-nitro-phenyl)corrolate; Joseph, C.; Ford, P. C. J. Am. Chem. Soc. 2005, 127, 6737-6743), the second-order rate constants, kNO, are all much faster ((1-9) × 108 M-1 s-1 at 298 K) than those for analogous iron(III)complexes of porphyrins. However, on a more microscopic level there is no obvious pattern in these rates withrespect to the donor properties of the aryl ring substituents. The high reactivity of the ferric triarylcorrolates with NOdata is interpreted in terms of the strongly electron-donating character of the Ar3C3- ligand and the quartet electronicconfiguration of the Fe(Ar3C) intermediate.
NO, whichmodestly decreased with the stronger donor substituents. Flash photolysis of Fe(Ar3C)(NO) solutions in tolueneleads to NO dissociation followed by rapid [NO]-dependent decay of the transients formed (presumably Fe(Ar3C))to regenerate the original spectra. As was seen in an earlier flash photolysis study of Fe(TNPC)(NO) (TNPC3- =5,10,15-tris(4-nitro-phenyl)corrolate; Joseph, C.; Ford, P. C. J. Am. Chem. Soc. 2005, 127, 6737-6743), the second-order rate constants, kNO, are all much faster ((1-9) × 108 M-1 s-1 at 298 K) than those for analogous iron(III)complexes of porphyrins. However, on a more microscopic level there is no obvious pattern in these rates withrespect to the donor properties of the aryl ring substituents. The high reactivity of the ferric triarylcorrolates with NOdata is interpreted in terms of the strongly electron-donating character of the Ar3C3- ligand and the quartet electronicconfiguration of the Fe(Ar3C) intermediate.