(F8TPP)FeII/O2 Reactivity Studies {F8TPP = Tetrakis(2,6-difluorophenyl)porphyrinate(2−)}:  Spectroscopic (UV−Visible and NMR) and Kinetic Study of Solvent-Dependent (Fe/O2 = 1:1 or 2:1) Reversible O2-Reduction and Ferryl Formation

Ghiladi, Reza A.; Kretzer, Ryan M.; Guzei, Ilia A.; Rheingold, Arnold L.; Neuhold, Yorck-Michael; Hatwell, Karen R.; Zuberbühler, Andreas D.; Karlin, Kenneth D.

doi:10.1021/ic0105866

Cited by 118 publications

(184 citation statements)

References 101 publications

Supporting

Mentioning

166

Contrasting

Order By: Relevance

“…The compounds (F 8 )Fe II ( 1 ) [35, 40, 41], (P Py )Fe II ( 2 ) [37, 38], and (P Im )Fe II ( 3 ) [37, 42] were synthesized as previously described.…”

Section: Methodsmentioning

confidence: 99%

Isocyanide or nitrosyl complexation to hemes with varying tethered axial base ligand donors: synthesis and characterization

et al. 2016

Self Cite

View full text Add to dashboard Cite

A series of ferrous-heme 2,6-dimethylphenyl isocyanide (DIMPI) and ferrous-heme mononitrosyl complexes have been synthesized and characterized. The heme portion of the complexes studied is varied with respect to the nature of the axial ligand, including complexes, where it is covalently tethered to the porphyrinate periphery. Reduced heme complexes, [(F8)FeII], [(PPy) FeII], [(PIm)FeII], and [(PImH)FeII], where F8 = tetrakis(2,6-difluorophenyl)-porphyrinate and PPy, PIm, and PImH are partially fluorinated tetraaryl porphyrinates with covalently appended axial base pyridyl/imidazolyl or histamine moieties, were employed; PImH is a new construct. Room temperature addition of DIMPI to these iron(II) complexes affords the bis-isocyanide species [(F8)FeII-(DIMPI)2] in the case of [(F8)FeII], while for the other hemes, mono-DIMPI compounds are obtained, [(PPy)FeII-(DIMPI)] [(2)-DIMPI], [(PIm)FeII-(DIMPI)] [(3)-DIMPI], and [(PImH) FeII-(DIMPI)] [(4)-DIMPI]. The structures of complexes (3)-DIMPI and (4)-DIMPI have been determined by single crystal X-ray crystallography, where interesting H…F(porphryinate aryl group) interactions are observed. 19F-NMR spectra determined for these complexes suggest that H…F(porphyrinate aryl groups) attractions also occur in solution, the H atom coming either from the DIMPI methyl groups or from a porphyinate axial base imidazole or porphyrinate pyrrole. Similarly, we have used nitrogen monoxide to generate ferrous-nitrosyl complexes, a five-coordinate species for F8, [(F8)FeII-(NO)], or low-spin six-coordinate compounds [(PPy)FeII-(NO)], [(PIm)FeII-(NO)], and [(PImH)FeII-(NO)]. The DIMPI and mononitrosyl complexes have also been characterized using UV–Vis, IR, 1H-NMR, and EPR spectroscopies.

show abstract

“…The compounds (F 8 )Fe II ( 1 ) [35, 40, 41], (P Py )Fe II ( 2 ) [37, 38], and (P Im )Fe II ( 3 ) [37, 42] were synthesized as previously described.…”

Section: Methodsmentioning

confidence: 99%

Isocyanide or nitrosyl complexation to hemes with varying tethered axial base ligand donors: synthesis and characterization

et al. 2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…[(tmpa)Cu II (NO 2 )][B(C 6 F 5 ) 4 ] [36], [(tmpa)Cu I (MeCN)][B(C 6 F 5 ) 4 ] [36], [(AN)Cu I ][B(C 6 F 5 ) 4 ] [43], and (F 8 )Fe II [37, 38] were synthesized and characterized following methods previously described in the literature. (TMPP)Fe III (Cl) were purchased from TriPorTech GmbH-Germany.…”

Section: Methodsmentioning

confidence: 99%

“…The copper complexes are [(tmpa)Cu II (NO 2 )][B(C 6 F 5 ) 4 ] (tmpa ≡ tris(2-pyridylmethylamine)[36] and a new compound [(AN)Cu II (NO 2 )](CF 3 SO 3 ) (AN ≡ 3,3’-iminobis ( N , N -dimethylpropylamine)); an X-ray crystal structure reveals the binding of nitrite to be different than that found for the tmpa containing complex. The hemes utilized in this study include the iron(II) complex (F 8 )Fe II (F 8 ≡ tetrakis(2,6-difluorophenyl)porphyrinate(2–))[37, 38] and a heme compound bearing an electron-rich porphyrinate, (TMPP)Fe II (TMPP ≡ tetrakis(4-methoxyphenyl)porphyrinate(2–)). As shown in Fig.…”

Section: Introductionmentioning

confidence: 99%

Nitric oxide generation from heme/copper assembly mediated nitrite reductase activity

2014

Self Cite

View full text Add to dashboard Cite

Nitric oxide (NO) as a cellular signaling molecule and vasodilator regulates a range of physiological and pathological processes. Nitrite (NO2−) is recycled in vivo to generate nitric oxide, particularly in physiologic hypoxia and ischemia. The cytochrome c oxidase (CcO) binuclear hemea3/CuB active site is one entity known to be responsible for cellular nitrite conversion to nitric oxide. We recently reported that a partially reduced heme/Cu assembly reduces nitrite ion, producing NO; the heme serves as the reductant and cupric ion provides a Lewis Acid interaction with nitrite, facilitating nitrite (N−O) bond cleavage (Hematian et al., J Am Chem Soc 134:18912–18915, 2012). To further investigate this nitrite reductase (NIR) chemistry, copper(II)-nitrito complexes with tri-and tetra-dentate ligands were used in this study, where either O,O'-bidentate or O-unidentate modes of nitrite binding to the cupric center are present. To study the role of the reducing ability of the ferrous heme center, two different tetraarylporphyrinate-iron(II) complexes, one with electron donating para-methoxy peripheral substituents, (TMPP)FeII, and the other with electron withdrawing 2,6-difluorophenyl substituents, (F8)FeII, were employed. The results show that differing nitrite coordination modes to copper(II) ion leads to varying kinetic behavior. Here, also, the ferrous heme is in all cases the source of the reducing equivalent required to take nitrite to nitric oxide, but the reduction ability of the heme center does not play a key role in the observed overall reaction rate. Based on our observations, reaction mechanisms are proposed and discussed in terms of heme/Cu heterobinuclear structures.

show abstract

“…For example, in work aimed at providing benchmark information for studies of models of cytochrome c oxidase (Section 2.3.1), reversible O 2 binding to the Fe(II) precursor of 9 was observed at À80 C ( Figure 4) [21]. Manometry confirmed the formation of a 1:1 O 2 /Fe adduct in tetrahydrofuran; however, in non-coordinating solvents the reversible formation of a μ-peroxo dimer was observed, as supported by a 1:2 O 2 /Fe stoichiometry [21]. More recently, compounds 10-12 have also been synthesized in which the axial solvent molecule has been replaced by a pendant imidazole or pyridyl ligand [22,23].…”

Section: Fe(iii)-superoxo Intermediatesmentioning

confidence: 99%

Transition Metal Complexes and the Activation of Dioxygen

Yee

Tolman

2014

Metal Ions in Life Sciences

View full text Add to dashboard Cite

In order to address how diverse metalloprotein active sites, in particular those containing iron and copper, guide O₂binding and activation processes to perform diverse functions, studies of synthetic models of the active sites have been performed. These studies have led to deep, fundamental chemical insights into how O₂coordinates to mono- and multinuclear Fe and Cu centers and is reduced to superoxo, peroxo, hydroperoxo, and, after O-O bond scission, oxo species relevant to proposed intermediates in catalysis. Recent advances in understanding the various factors that influence the course of O₂activation by Fe and Cu complexes are surveyed, with an emphasis on evaluating the structure, bonding, and reactivity of intermediates involved. The discussion is guided by an overarching mechanistic paradigm, with differences in detail due to the involvement of disparate metal ions, nuclearities, geometries, and supporting ligands providing a rich tapestry of reaction pathways by which O₂is activated at Fe and Cu sites.

show abstract

(F₈TPP)Fe^II/O₂ Reactivity Studies {F₈TPP = Tetrakis(2,6-difluorophenyl)porphyrinate(2−)}: Spectroscopic (UV−Visible and NMR) and Kinetic Study of Solvent-Dependent (Fe/O₂ = 1:1 or 2:1) Reversible O₂-Reduction and Ferryl Formation

Cited by 118 publications

References 101 publications

Isocyanide or nitrosyl complexation to hemes with varying tethered axial base ligand donors: synthesis and characterization

Isocyanide or nitrosyl complexation to hemes with varying tethered axial base ligand donors: synthesis and characterization

Nitric oxide generation from heme/copper assembly mediated nitrite reductase activity

Transition Metal Complexes and the Activation of Dioxygen

Contact Info

Product

Resources

About