Reaction of pentafluoronitrosobenzene with [Os3(CO)11(CH3CN)] and high-performance liquid chromatographic separation of [Os3(CO)11(μ-ONC6F5)], [Os3(CO)9(μ3-NC6F5)2], [Os3(CO)11(CH3CN)] and Os3(CO)12

Ang, H.G.; Kwik, W.L.; Ong, Kate K.

doi:10.1016/s0022-1139(00)82193-4

Cited by 11 publications

(6 citation statements)

References 6 publications

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“…Work of Berman and Kochi on the deoxygenation of nitroarenes by nickel phosphine complexes (eq 3) provided kinetic evidence for a single-electron transfer pathway and suggested that a side-bound nitrosoarene nickel complex was formed. Side-bound nitrosoarene complexes have been previously isolated and characterized in mono-metallic complexes − and in metal clusters. − These complexes have been suggested to be important intermediates in the homogeneous catalytic carbonylation of nitroaromatics . In the current study we provide kinetic evidence that the initial deoxygenation proceeds via rate-determining inner-sphere electron transfer.…”

Section: Introductionmentioning

confidence: 63%

Activation of Nitroarenes in the Homogenous Catalytic Carbonylation of Nitroaromatics via an Oxygen-Atom-Transfer Mechanism Induced by Inner-Sphere Electron Transfer

Skoog

Gladfelter

1997

J. Am. Chem. Soc.

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Kinetic and mechanistic studies on the deoxygenation of nitroarenes by Ru(dppe)(CO)3, where dppe = 1,2-bis(diphenylphosphino)ethane, are described. The products of the reaction included 1 equiv of carbon dioxide and an η2-nitrosoarene ruthenium complex (Ru(dppe)(CO)2[ON(Ar)] for Ar = 4-chloro-2-trifluoromethylphenyl), which was isolated and fully characterized by solution spectroscopic methods and by single crystal X-ray diffraction [monoclinic crystal system, space group P21/c (#14), a = 14.556 (8) Å, b = 12.903 (6) Å, c = 20.10 (1) Å, β = 105.60 (6)°, V = 3636 (8) Å3, Z = 4]. The deoxygenation reaction was determined to be first-order with respect to both Ru(dppe)(CO)3 and nitroarene. Electron withdrawing substituents on the nitroarene and polar solvents accelerated the rate, and a substituent study provided a ρ of +3.45 indicating negative charge buildup on the nitroarene in the rate determining step of the reaction. Activation enthalpies for 2-CF3, 4-Cl, 4-H, and 4-CH3 substituted nitroarenes were 9.3, 9.9, 10.5, and 10.7 kcal mol-1, and the entropies of activation were −35, −33, −36, and −37 eu, respectively. Correlation between the reduction potentials of the nitroarenes (E°ArNO2) and log k 2 was also observed for substituted nitroarenes yielding a slope of 10 V-1. Monosubstituted nitroarenes bearing a single methyl, phenyl, or chloro group in the ortho position and disubstituted 2,6-dimethyl- and 2,3-dichloronitrobenzene showed no attenuation in the rate, from what would be expected based on the E°ArNO2 − log k 2 correlation. Large rate attenuation was observed for nitroarenes bearing both ortho and meta groups. Analysis of the kinetic and thermodynamic data using Marcus theory indicated that the rates were too high for an outer-sphere electron-transfer mechanism. The data were interpreted in terms of an inner-sphere electron-transfer mechanism where the unfavorable energetics are mitigated by bonding interactions between the donor and acceptor.

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Section: Introductionmentioning

confidence: 63%

Activation of Nitroarenes in the Homogenous Catalytic Carbonylation of Nitroaromatics via an Oxygen-Atom-Transfer Mechanism Induced by Inner-Sphere Electron Transfer

Skoog

Gladfelter

1997

J. Am. Chem. Soc.

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“…Several types of bridging coordination modes have been found for C -nitroso compound ligands in multinuclear transition metal complexes, 8b,− where the μ-η 1 :η 2 - N , O coordination mode has been observed most commonly. 8b, As described above, complexes 8 − 10 are classified as less common μ-η 1 :η 1 - N , O complexes. , The N−O bond distances found in 8 (1.353(5) Å), 9b (1.333(6) Å), and 10b (1.339(8) Å) are longer than the NO double bond distances of free nitrosoarene monomers (1.21−1.28 Å) 25 and are comparable to the values reported for the μ-η 1 :η 1 - N , O nitrosoarene ligands in ruthenium clusters [Ru 3 (μ-ONC 10 H 6 O) 2 (CO) 8 ] (1.30(1), 1.31(1) Å) 22a and [Ru 3 (μ-NPh) 2 (μ-PhNO) 2 (CO) 7 ] (1.334(9) Å) 22b but are considerably shorter than that described for the nitrosobenzene ligand of this type in [(Me 3 P) 2 Pt(μ-η 1 :η 1 -PhNO)(μ-η 1 -PhNO)Pt(PhNO)(PMe 3 )] (1.433(15) Å) 22c. It should be noted that the μ-η 1 :η 1 -PhNO ligand in the last complex is regarded as a dianionic ligand with an N−O single bond.…”

Section: Resultsmentioning

confidence: 98%

Preparation of Cationic Dinuclear Hydrido Complexes of Ruthenium, Rhodium, and Iridium with Bridging Thiolato Ligands and Their Reactions with Nitrosobenzene

et al. 1999

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A series of cationic dinuclear hydrido complexes with bridging thiolato ligands [CpMH(&mgr;-SPr(i))(2)MCp][OTf] (4, M = Ru; 6a, M = Rh; 7a, M = Ir; Cp = eta(5)-C(5)Me(5), OTf = OSO(2)CF(3)) were synthesized by treatment of the corresponding chloro complexes [CpRuCl(&mgr;-SPr(i))(2)Ru(OH(2))Cp][OTf] (1) or [CpM(&mgr;-Cl)(&mgr;-SPr(i))(2)MCp][OTf] (2, M = Rh; 3, M = Ir) with HSiEt(3). The dirhodium and diiridium complexes 6 and 7 have been shown to possess a bridging hydrido ligand by crystallographic analysis, while the diruthenium complex 4 is proposed to have a terminal hydrido ligand that undergoes facile migration between the two ruthenium centers in solution. Complexes 4, 6a, and 7a reacted with nitrosobenzene to give the paramagnetic dinuclear nitrosobenzene complexes [CpM(&mgr;-PhNO)(&mgr;-SPr(i))(2)MCp](+) (M = Ru, Rh, Ir) along with azoxybenzene. The molecular structures of the three nitrosobenzene complexes have been determined by X-ray diffraction study to reveal that in each case nitrosobenzene acts as a &mgr;-eta(1):eta(1)-N,O ligand. Judging from the molecular structures and the ESR spectra, the unpaired electron is considered to be located mainly on the nitrosobenzene ligand, at least in the diruthenium and dirhodium complexes. On the other hand, complex 2 reacted with nitrosobenzene to give the incomplete cubane-type trinuclear cluster [(CpRh)(3)(&mgr;-Cl)(2)(&mgr;(3)-S)(&mgr;-SPr(i))](+), whose molecular structure has also been determined crystallographically.

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“…(v) Alongside several ArNO 2– examples (N–O = 1.40–1.53 Å), ,− dinuclear μ-η 2 :η 1 complexes have been found in the solid-state structures of Cu complexes with shorter NO bond lengths (1.322–1.375 Å). , Typically, the 1e-reduced ArNO •– moiety binds η 2 to a Cu(II) center and η 1 to a Cu(I) center (Scheme e). These species are thought to be in equilibrium with the mononuclear form [Cu II (η 2 -ArNO •– )] in solution. , …”

Section: Introductionmentioning

confidence: 99%

Tuning Inner-Sphere Electron Transfer in a Series of Copper/Nitrosoarene Adducts

et al. 2020

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A series of copper/nitrosoarene complexes were created that mimic several steps in biomimetic O 2 activation by copper(I). The reaction of the copper(I) complex of N,N,N′,N′tetramethypropylenediamine with a series of para-substituted nitrosobenzene derivatives leads to adducts in which the nitrosoarene (ArNO) is reduced by zero, one, or two electrons, akin to the isovalent species dioxygen, superoxide, and peroxide, respectively. The geometric and electronic structures of these adducts were characterized by means of X-ray diffraction, vibrational analysis, ultraviolet−visible spectroscopy, NMR, electrochemistry, and density functional theory (DFT) calculations. The bonding mode of the NO moiety depends on the oxidation state of the ArNO moiety: κN for ArNO, mononuclear η 2-NO and dinuclear μ-η 2 :η 1 for ArNO •− , and dinuclear μ-η 2 :η 2 for ArNO 2−. 15 N isotopic labeling confirms the reduction state by measuring the NO stretching frequency (1392 cm −1 for κN-ArNO, 1226 cm −1 for η 2-ArNO •− , 1133 cm −1 for dinuclear μ-η 2 :η 1-ArNO •− , and 875 cm −1 for dinuclear μ-η 2 :η 2 for ArNO 2−). The 15 N NMR signal disappears for the ArNO •− species, establishing a unique diagnostic for the radical state. Electrochemical studies indicate reduction waves that are consistent with one-electron reduction of the adducts and are compared with studies performed on Cu-O 2 analogues. DFT calculations were undertaken to confirm our experimental findings, notably to establish the nature of the charge-transfer transitions responsible for the intense green color of the complexes. In fine, this family of complexes is unique in that it walks through three redox states of the ArNO moiety while keeping the metal and its supporting ligand the same. This work provides snapshots of the reactivity of the toxic nitrosoarene molecules with the biologically relevant Cu(I) ion. 47 usually too oxidative to be stable above −60°C.

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Reaction of pentafluoronitrosobenzene with [Os3(CO)11(CH3CN)] and high-performance liquid chromatographic separation of [Os3(CO)11(μ-ONC6F5)], [Os3(CO)9(μ3-NC6F5)2], [Os3(CO)11(CH3CN)] and Os3(CO)12

Cited by 11 publications

References 6 publications

Activation of Nitroarenes in the Homogenous Catalytic Carbonylation of Nitroaromatics via an Oxygen-Atom-Transfer Mechanism Induced by Inner-Sphere Electron Transfer

Activation of Nitroarenes in the Homogenous Catalytic Carbonylation of Nitroaromatics via an Oxygen-Atom-Transfer Mechanism Induced by Inner-Sphere Electron Transfer

Preparation of Cationic Dinuclear Hydrido Complexes of Ruthenium, Rhodium, and Iridium with Bridging Thiolato Ligands and Their Reactions with Nitrosobenzene

Tuning Inner-Sphere Electron Transfer in a Series of Copper/Nitrosoarene Adducts

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