34690-41-0Relevant articles and documents
Isolation, X-ray crystal structure, and reactivity of a new C-H carbene complex of (5,10,15,20-tetraphenylporphyrinato)ruthenium(II)
Maux, Paul Le,Roisnel, Thierry,Nicolas, Irene,Simonneaux, Gerard
, p. 3037 - 3042 (2009/02/05)
The new (porphyrin)ruthenium(II) carbene complex 1 has been prepared by treating (TPP)Ru(CO)(EtOH) with excess 2,6-di-tert-butyl-4-methylphenyl diazoacetate and characterized by X-ray crystal structure analysis due to a kinetic stability. The reactivity of 1 toward axial ligands (CO, pyridine, dimethylphenylphosphine) and the asymmetric cyclopropanation of styrene with this bulky diazoacetate ester catalyzed by ruthenium Halterman porphyrin are also presented.
Synthesis and Structural Characterization of Several Ruthenium Porphyrin Nitrosyl Complexes
Miranda, Katrina M.,Bu, Xianhui,Lorkovic, Ivan,Ford, Peter C.
, p. 4838 - 4848 (2008/10/09)
The synthesis, X-ray crystal structures, and some spectroscopic and chemical properties of the nitrosylruthenium(II) porphyrin complexes Ru(TPP) (NO) (ONO), Ru(TPP) (NO) (OH), Ru(OEP) (NO) (ONO), and Ru(OEP) (NO)-(OH) (TPP = tetraphenylporphyrinato dianion; OEP = octaethylporphyrinato dianion) derived from the analogous Ru(II) carbonyl complexes are reported. Also described are experiments which quantitatively demonstrate that N2O is formed as a product of the synthesis scheme and that NO serves as the principal oxidant in the transformation of N(II) to N(III). The two TPP complexes are isostructural and consist of columns of molecules stacked along the c axis. The two OEP complexes are also isostructural and can be considered as layers of OEP complexes stacked along the b axis with solvent molecules situated at the cavities between layers. The nitrite ions are coordinated in a unidentate fashion through the oxygen atom. Crystal data for Ru(TPP) (NO) (ONO) (1): M = 789.79, space group I4/m (No. 87), a = 13.6529(6) A, c = 9.7904(5) A, V = 1825.0(2) A3, Z = 2, ρ = 1.437 g cm-3, purple bipyramid, 2θmax = 50.0°, R(F) = 4.87% for 86 parameters and 838 reflections with I > 2σ(I). Crystal data for Ru(TPP) (NO) (OH) (2): M = 760.79, space group I4/m (No. 87), a = 13.5423(4) A, c = 9.7150-(4) A, V= 1781.7(1) A3, Z = 2, ρ = 1 .418 g cm-3, dark red plate, 2θmax = 50.0°, R(F) = 3.92% for 83 parameters and 811 reflections with I > 2σ(I). Crystal data for Ru(OEP) (NO)(ONO)·CH2Cl2 (3): M = 794.77, space group P21 (No. 4), a = 10.7687(2) A, b = 21.0320(2) A, c = 8.5936(2) A, β= 102.683(1)°, V= 1898.85(6) A3, Z = 2, ρ = 1.390 g cm-3, black plate, 2θmax = 50.0°, R(F) = 6.23% for 453 parameters and 4702 reflections with I > 2σ(I). Crystal data for Ru(OEP) (NO) (OH)·C2H5OH (4): M = 726.91, space group P21 (No. 4), a = 10.8474-(7) A, b = 21.002(1) A, c = 8.3646(5) A, β= 103.571(1)°, V= 1852.4(2) A3, Z= 2, ρ = 1.303 g cm-3, brown plate, 2θmax = 45.0°, R(F) = 6.74% for 421 parameters and 3527 reflections with I > 2σ(I).
Synthesis and Magnetic Exchange Properties of Linear Trinuclear Oxo- Bridged M(III)ORu(IV)OM(III) Complexes (M = Fe, Cr, Mn) Formed by Two-Electron Redox Reactions
Berry, Kevin J.,Moubaraki, Boujemaa,Murray, Keith S.,Nichols, Peter J.,Schulz, Lewis D.,West, Bruce O.
, p. 4123 - 4133 (2008/10/08)
The two-electron reductions of various porphyrin complexes Ru(VI)(O)2(P) by Fe(II), Cr(II), and Mn(II) compounds of porphyrins and salicylaldimines result in the formation of heterotrimetallic oxo-bridged complexes (L)M(III)ORu(IV)(P)OM(III)(L) (M = Fe(III), Cr(III), Mn(III); P is the dianion of 5,10,15,20-tetraarylporphyrins, such as tetraphenylporphyrin (TPP), tetrakis(p-methoxyphenyl)porphyrin (TMP), or 2,3,7,8,12,13,17,18-octaethylporphyrin (OEP); L is TPP, TMP, or OEP or the dianions of N,N'-(4-methyl-4-azaheptane-1,7-diyl)bis(salicylaldimine) (salmah) or N,N'-ethane-1,2-diylbis(salicylaldimine) (salen). A detailed study of the temperature- and field-dependent magnetic properties of this rather novel series of (L)M(III)ORu(IV)(P)OM(III)(L) compounds has been made. The spin-states of the constituent metal centers are as follows: Ru(IV), SRu = 1 (d(4)); Fe(III), SFe = 5/2 (d(5)); Cr(III), SCr = 3/2 (d(3)); Mn(III), SMn= 4/2 (d(4)). The spin-state and coordination geometry of the (L)Fe(III) groups were confirmed by Moessbauer spectral measurements. Trinuclear combinations of the present kind give rise to unusual coupled spin-stateenergy levels which, in the case of (L)Fe(III)ORu(IV)(P)OFe(III)(L) compounds, result in "ferromagnetic-like" plots of magnetic moment versus temperature, particularly at low temperatures. The following best-fit values of parameters were deduced from the magnetic moment data, obtained in 1 T fields over the temperature range 4.2-300 K. (salmah)FeORu(TPP)OFe(salmah): g = 1.97, J12 = -19.7 cm**-1, J13 = +6.5 cm**-1, α = J13/J12 = -0.33, ground-state S = 4; (TMP)FeORu(TPP)OFe(TMP): g = 1.95, J12= -23.4 cm**-1, J13 = 5.4 cm**- 1, α = -0.23, ground-state S = 4.(TPP)FeORu(TPP)OFe(TPP): g = 2.0, J12 = -35.7 cm**-1, J13 = 11.2 cm**-1, α = -0.31, ground-state S = 4, [(TPP)Fe]2O impurity = 13%, zero-field splitting of the S = 4 state (D ~ 5 cm**-1). (TMP)MnORu(TPP)OMn(TMP): g = 1.93, J12 = -17.4 cm**-1, J13 = 9.6 cm**-1, α = -0.55, ground-state S = 3. (TPP)CrORu(TPP)OCr(TPP): g = 1.98, J12 = -25.3 cm**-1, J13 = -11.1 cm**-1, α = 0.44, ground-state S = 1. Possiblereasons for the small sizes of the J12 values, in comparison to those of related M(III)OM(III) and Ru(IV)ORu(IV) compounds, are discussed.
Axial-Ligand Control of the Photophysical Behavior of Ruthenium(II) Tetraphenyl- and Octaethylporphyrin. Contrasting Properties of Metalloporphyrin (?,?*) and (d,?*) Excited States
Levine, Leanna M. A.,Holten, Dewey
, p. 714 - 720 (2007/10/02)
The photophysical behavior of the ruthenium(II) porphyrins depends dramatically on the axial ligands coordinated to the central metal ion.We have measured the picosecond and slower time scale transient absorption spectra and kinetics, emission data, and ground-state absorption spectra for two classes of complexes: RuP(CO)(L) and RuP(L)2.Results are compared for complexes in which the porphyrin macrocycle (P) is tetraphenylporphyrin (TPP) or octaethylporphyrin (OEP) and the axial ligand L is piperidine (pip), pyridine (py), dimethyl sulfoxide (Me2SO), or ethanol (EtOH).We assign the lowest excited state of all the RuP(CO)(L) complexes, including those with L absent, as the lowest excited triplet state 3(?,?*), of the porphyrin ring 3(?,?*) appears to form in high yield from the ring excited singlet, 1(?,?*), in a metal-to-ring (d,?*) charge-transfer (CT) state.We attribute this general switch of the lowest excited state from 3(?,?*) in RuP(CO)(L) to (d,?* in RuP(L)2 to the loss of ?-backbonding between the filled Ru(d?) orbitals and the empty CO(?*) orbitals.The loss of axial ?-backbonding is expected to destabilize the d? orbitals, making them closer in energy to the empty eg(?*) orbitals of the porphyrin ring.This lowers the energy of (d,?*) relative to 3(?,?*) in RuP(L)2 compared to RuP(CO)(L).Although 3(?,?*) appears to be the lowest excited state in all the RuP(CO)(L) complexes investigated, we propose that the deactivation of this state nonetheless proceeds, in part, via a shorter lived (d,?*) state at higher energy.We speculate that the faster decay of (d,?*) compared to 3(?,?*) may be due to a better Franck-Condon factor for radiationless decay to the ground state.The recay route of 3(?.?*) via a thermally accessible (d,?*) in the RuP(CO)(L) complexes also may be the pathway for photodissociation of CO from these molecules, which in the presence of L results in the formation of RuP(L)2.The photodissociation quantum yield is measured to be ca. 1E-4 for two of the complexes.
