Synthesis and Spectroscopy of -Oxo (O2-)-Bridged Heme/Non-heme Diiron Complexes: Models for the Active Site of N
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- 作者：Ian M. Wasser ; Constantinus F. Martens ; Claudio N. Verani ; Eva Rentschler ; Hong-wei Huang ; Pierre Moë ; nne-Loccoz ; Lev N. Zakharov ; Arnold L. Rheingold ; and Kenneth D. Karlin
- 刊名：Inorganic Chemistry
- 出版年：2004
- 出版时间：January 26, 2004
- 年：2004
- 卷：43
- 期：2
- 页码：651 - 662
- 全文大小：233K
- 年卷期：v.43,no.2(January 26, 2004)
- ISSN：1520-510X
文摘
In this paper, we describe the synthesis and study of a series of heme/non-heme Fe-O-Fe' complexes supportedby a porphyrin and the tripodal nitrogen ligand TMPA [TMPA = tris(2-pyridylmethyl)amine]. The complete synthesisof [(6L)Fe-O-Fe(X)]+ (1) (X = OMe- or Cl-, 69:31 ratio), where 6L is the dianion of 5-(o-O-[(N,N-bis(2-pyridylmethyl)-2-(6-methoxyl)pyridinemethanamine)phenyl]-10,15,20-tris(2,6-difluorophenyl)porphine, is reported. The crystal structurefor 1·PF6 reveals an intramolecular heme/non-heme diferric complex bridged by an Fe-O-Fe' moiety; 
ntities/ang.gif">(Fe-O-Fe') = 166.7(3)ntities/deg.gif">, and d(Fe···Fe') = 3.556 Å. Crystal data for C70H57ClF12Fe2N8O3P (1·PF6): triclinic, Pntities/onemacr.gif">, a =13.185(3) Å, b = 14.590 (3) Å, c = 16.885(4) Å, 
= 104.219(4)ntities/deg.gif">, 
= 91.572(4)ntities/deg.gif">, 
= 107.907(4)ntities/deg.gif">, V =2977.3(11) Å3, Z = 2, T = 150(2) K. Complex 1 (where X = Cl-) is further characterized by UV-vis (
max = 328,416 (Soret), 569 nm), 1H NMR (
27-24 [TMPA -CH2-], 16.1 [pyrrole-H], 15.2-10.5 [PY-3H, PY-5H], 7.9-7.2 [m-and p-phenyl-H], 6.9-5.8 [PY-4H] ppm), resonance Raman (
nu.gif" BORDER=0 >as(Fe-O-Fe') 844 cm-1), and Mössbauer (Fe =0.47, 0.41 mm/s; 
EA = 1.59, 0.55 mm/s; 80 K) spectroscopies, MALDI-TOF mass spectrometry (m/z 1202), andSQUID susceptometry (J = - 114.82 cm-1, S = 0). We have also synthesized a series of 3-, 4-, and 5-methyl-substituted as well as selectively deuterated TMPA(Fe') complexes and condensed these with the hydroxo complex(F8)FeOH or (F8-d8)FeOH to yield "untethered" Fe-O-Fe' analogues. Along with selective deuteration of the methylenehydrogens in TMPA, complete 1H NMR spectroscopic assignments for 1 have been accomplished. The magneticproperties of several of the untethered complexes and a comparison to those of 1 are also presented. Complex 1and related species represent good structural and spectroscopic models for the heme/non-heme diiron active sitein the enzyme nitric oxide reductase.
ntities/ang.gif">(Fe-O-Fe') = 166.7(3)ntities/deg.gif">, and d(Fe···Fe') = 3.556 Å. Crystal data for C70H57ClF12Fe2N8O3P (1·PF6): triclinic, Pntities/onemacr.gif">, a =13.185(3) Å, b = 14.590 (3) Å, c = 16.885(4) Å, = 104.219(4)ntities/deg.gif">, = 91.572(4)ntities/deg.gif">, = 107.907(4)ntities/deg.gif">, V =2977.3(11) Å3, Z = 2, T = 150(2) K. Complex 1 (where X = Cl-) is further characterized by UV-vis (max = 328,416 (Soret), 569 nm), 1H NMR ( 27-24 [TMPA -CH2-], 16.1 [pyrrole-H], 15.2-10.5 [PY-3H, PY-5H], 7.9-7.2 [m-and p-phenyl-H], 6.9-5.8 [PY-4H] ppm), resonance Raman (nu.gif" BORDER=0 >as(Fe-O-Fe') 844 cm-1), and Mössbauer (Fe =0.47, 0.41 mm/s; EA = 1.59, 0.55 mm/s; 80 K) spectroscopies, MALDI-TOF mass spectrometry (m/z 1202), andSQUID susceptometry (J = - 114.82 cm-1, S = 0). We have also synthesized a series of 3-, 4-, and 5-methyl-substituted as well as selectively deuterated TMPA(Fe') complexes and condensed these with the hydroxo complex(F8)FeOH or (F8-d8)FeOH to yield "untethered" Fe-O-Fe' analogues. Along with selective deuteration of the methylenehydrogens in TMPA, complete 1H NMR spectroscopic assignments for 1 have been accomplished. The magneticproperties of several of the untethered complexes and a comparison to those of 1 are also presented. Complex 1and related species represent good structural and spectroscopic models for the heme/non-heme diiron active sitein the enzyme nitric oxide reductase.