Role of ferryl (FeO2+) complexes in oxygen atom transfer reactions. Mechanism of iron(II) porphyrin catalyzed oxygenation of triphenylphosphine

Chin, Daeje; Mar, Gerd N. La; Balch, Alan L.

doi:10.1021/ja00538a059

Cited by 112 publications

(77 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Examples of sulfur [82,102], nitrogen [103], and phosphorus [76] oxidation have also been observed. It was originally proposed that epoxidation was carried out by an Fe(IV)-oxo π* cationradical species [101].…”

Section: O-atom Transfer Reactivitymentioning

confidence: 91%

“…Fe(IV)-oxo intermediates containing neutral porphyrin rings have also been prepared (25a-c, 26, and 27) ( Figure 9), and were first observed in the decomposition of (η 1 :η 2 -peroxo)diiron intermediates [75,76]. More recently, electrochemical preparation of 27 has been achieved by the one-electron oxidation of the Fe(III)-OH precursor [77].…”

Section: Fe(iv)-oxo Intermediatesmentioning

confidence: 99%

See 1 more Smart Citation

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

Section: O-atom Transfer Reactivitymentioning

confidence: 91%

Section: Fe(iv)-oxo 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

show abstract

“…On the basis of Mössbauer spectra, all structures with Fe(IV) ions would be ruled out because the isomer shift is out of range for Fe(IV) complexes [34,35]. The electronic spectra also disagree with this hypothesis: (i) there are no bands in the electronic spectrum of form '630' which may be assigned to the well-characterized phthalocyanine cation radical [36][37][38][39][40]; (ii) to our knowledge, only monomeric oxygencontaining Fe(IV) complexes with porphyrin-like ligands are described [41][42][43][44]. The electronic spectrum of form '630' is typical for m-oxo-bridged phthalocyanine complexes [45][46][47][48][49][50], so all monomeric structures would be ruled out.…”

Section: Chemical Behaviormentioning

confidence: 99%

Further Studies on the Oxidation State of Iron in μ-Oxo Dimeric Phthalocyanine Complexes

Nemykin¹,

Chernii²,

Волков³

et al. 1999

J. Porphyrins Phthalocyanines

View full text Add to dashboard Cite

The reaction with sodium cyanide of the μ-oxo-bridged complex of tetra-4-tert-butyl-substituted iron phthalocyanine (form ‘690’) and that of the product of its treatment with organic bases such as Py, Im, etc. (form ‘627’) result in the formation of the same ferrous bis-cyanide complex Na 2[ Pc t Fe II ( CN )2] which can be readily oxidized to the analogous ferric complex Na [ Pc t Fe III ( CN )2]. Form ‘690’ has been oxidized to the corresponding ferric μ-oxo complex (form ‘630’). Data for all μ-oxo-bridged complexes (chemical behavior; electronic, NMR, Mössbauer, X-ray photoelectron and ESR spectra; magnetic susceptibility) are discussed, and based on them, the following structures are proposed: ( HPc t Fe II )2 O (form ‘690’), H 2[( LPc t Fe II )2 O ] (form ‘627’) and ( Pc t Fe III )2 O (form ‘630’).

show abstract

“…One plausible oxidation product [Fe(TPP)],O (20, 37) is ruled out because the Soret maximum of the p-0x0 species in CH2C12 is seen at 403 nm; a less likely product Fe(TPP)Cl exhibits the Soret maximum at 418 nm in CH2C12. The "oxidized" solution may well contain the five-coordinate phosphine oxide complex Fe(TPP)-(O=PnBu3); the corresponding triphenylphosphine oxide species is said to result from treatment of in situ Fe(TPP)(PPh3), with 02, but no characterization details were presented (37). The 415 nm species could be readily reconverted to 1 by treatment with PnBu3.…”

Section: Decarbonylation Of Aldehydesmentioning

confidence: 99%

“…Oxygenated species such as trace amounts of FeI1O2 (Fe1I1O~) could act as a chain initiator; H atom abstraction would then give coordinated [4] RCHO + ~e"'+ RCO + ~e " + H+ or free HOT., and such a reaction has been suggested previously (42). The 02-oxidation of Fe(I1) porphyrin phosphine species involves bridged-peroxo and 0x0 intermediates (37), and H-abstraction by either of these seems plausible (37,43). Trace protons (from water) can promote formation of superoxide (stabilized as H02.)…”

Section: Speculation On Mechanismsmentioning

confidence: 99%

Catalytic decarbonylation of aldehydes using iron(II) porphyrin complexes, and the crystal structure of (5,10,15,20-tetraphenylporphinato)bis(tri-n-butylphosphine)iron(II)

Belani¹,

James²,

Dolphin³

et al. 1988

Can. J. Chem.

View full text Add to dashboard Cite

The complex (5,10,15,20-tetraphenylporphinato)bis(tri-n-butylphosphine)iron(II), 1, has been isolated in a triclinic crysgl form, a = 12.499(3), b = 12.528(2), c = 12.039(2) A, u = 116.39(1), P = 109.79(1), y = 98.13(1)", Z = 1, spacegroup P1.The structure was solved by conventional heavy atom methods and was refined by full-matrix least-squares procedures to R = 0.060 and R,, = 0.070 for 3551 reflections with I ? 3 u(l). The molecule, which has crystallographic 1-Ci symmetry, displays a relatively undistorted pseudo-octahedral coordination geometry with Fe-P = 2.346(1) and Fe-N = 1.998(3) and 1.993(3) A.In CH2C1, solution, 1 reacts with CO and aldehydes to generate the carbonyl(phosphine) derivative, and decarbonylation of phenylacetaldehyde to toluene becomes catalytic under an Ar stream. The aldehyde decarbonylations involve radical pathways via carbonyl loss from PhCH2C0. The hydrogen abstraction/initiation reaction probably utilizes trace O2 (and possibly trace (water); speculative mechanisms are discussed. [Traduit par la revue] Introduction Carbonylation reactions provide key steps in a range of homogeneously catalyzed processes of industrial importance (1, 2). Decarbonylation (for example, of aldehydes: RCHO +

show abstract

Role of ferryl (FeO2+) complexes in oxygen atom transfer reactions. Mechanism of iron(II) porphyrin catalyzed oxygenation of triphenylphosphine

Cited by 112 publications

References 3 publications

Transition Metal Complexes and the Activation of Dioxygen

Transition Metal Complexes and the Activation of Dioxygen

Further Studies on the Oxidation State of Iron in μ-Oxo Dimeric Phthalocyanine Complexes

Catalytic decarbonylation of aldehydes using iron(II) porphyrin complexes, and the crystal structure of (5,10,15,20-tetraphenylporphinato)bis(tri-n-butylphosphine)iron(II)

Contact Info

Product

Resources

About