32073-84-0Relevant academic research and scientific papers
The Insertion of Ruthenium into Porphyrins Revisited and Improved: Proof of Concept Results with a Ruthenium(II) Monocarbonyl Compound, and the Spectacular Effect of Propionic Acid
Vidal, Alessio,Battistin, Federica,Iengo, Elisabetta,Milani, Barbara,Alessio, Enzo
, p. 2883 - 2890 (2019/06/24)
This contribution, that readdresses the insertion of the RuII–CO fragment into model porphyrins (i.e. ruthenation), has a Janus character, with one speculative and one practical side. As a proof of concept we demonstrate that ruthenation of a porphyrin can be performed under relatively mild conditions using the RuII monocarbonyl complex [Ru(CO)(dmso)5][PF6]2 that – besides CO – features exclusively labile dmso ligands. Even though this finding might seem trivial, it is only the second example that uses a RuII carbonyl for porphyrin ruthenation, the first one having been reported almost 50 years ago and then neglected. From a practical point of view, we show the spectacular effect of propionic acid as solvent for performing the ruthenation of neutral and anionic model porphyrins with Ru3(CO)12 (1). This process turned out to be extremely efficient and advantageous in terms of both reaction rates and yields (e.g. 100 % ruthenation of TPP in 30 min at 140 °C) compared to the procedures described in the literature.
A ruthenium porphyrin-based porous organic polymer for the hydrosilylative reduction of CO2 to formate
Eder, Grace M.,Pyles, David A.,Wolfson, Eric R.,McGrier, Psaras L.
supporting information, p. 7195 - 7198 (2019/07/02)
A ruthenium porphyrin-based porous organic polymer (POP) was synthesized, characterized, and used to reduce CO2 to a formate salt. We demonstrate that Ru-BBT-POP can be utilized to reduce CO2 to a silyl formate and then converted to potassium formate with a respectable turnover number and frequency.
Auxiliary-directed oxidation of ursolic acid by 'Ru'-porphyrins: Chemical modulation of cytotoxicity against tumor cell lines
Tanaka, Katsunori,Mazumder, Kishor,Siwu, Eric R.O.,Nozaki, Satoshi,Watanabe, Yasuyoshi,Fukase, Koichi
supporting information; experimental part, p. 1756 - 1759 (2012/05/04)
Derivatization of ursolic acid, one of the natural ursene-type pentacyclic triterpenes, was investigated by the oxidation with dioxoruthenium(VI) tetraphenylporphyrins. Oxidation selectivity on the terpene structure was modulated by the auxiliaries introd
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.
Structural determination of ruthenium-porphyrin complexes relevant to catalytic epoxidation of olefins
Gallo, Emma,Caselli, Alessandro,Ragaini, Fabio,Fantauzzi, Simone,Masciocchi, Norberto,Sironi, Angelo,Cenini, Sergio
, p. 2039 - 2049 (2008/10/09)
A reproducible synthesis of a competent epoxidation catalyst, [Ru VI(TPP)(O)2] (TPP = tetraphenylporphyrin dianion), starting from [RuII(TPP)(CO)L] (L = none or CH3OH), is described. The molecular structure of the complex
Synthesis and Electrochemical Characterization of Ruthenium Porhyrins containing a Bound PF3 Axial Ligand
Kadish, Karl M.,Hu, Yu,Tagliatesta, Pietro,Boschi, Tristano
, p. 1167 - 1172 (2007/10/02)
The first synthesis and electrochemistry of metalloporphyrins containing a bound PF3 axial ligand has been achieved.The investigated compounds are where por is the dianion of 5,10,15,20-tetraphenyl-, -tetra(p-bromophenyl)-, -tetra(p-methoxyphenyl)-, 2,7,12,17-tetraethyl-3,8,13,18-tetramethyl- or 2,3,7,8,12,13,17,18-octaethyl-porphyrin.Each species was investigated with respect to its spectroscopic and electrochemical properties and the resulting data compared with those for having the same porphyrin ring.A number of similarities exist between the carbonyl and PF3 derivatives in methylene chloride but major differences can be observed in other non-aqueous solutions.The first reduction of each complex is reversible in tetrahydrofuran (thf) and leads to a porphyrin ?-anion radical rather than a ruthenium(I) species as identified by UV/VIS spectroelectrochemistry.Each investigated complex also undergoes two reversible oxidations in dichloromethane, the first of which leads to a porphyrin ?-cation radical.The derivatives appear to be more stable than the analogues in thf or CH2Cl2, but an electrochemically initiated conversion of II(por)(PF3)(py)> into III(Por)(py)2>(1+) can be readily accomplished in pyridine (py) or CH2Cl2-pyridine mixtures.This type of reaction has never been seen upon oxidation of a ruthenium(II) porphyrin and was monitored by cyclic voltammetry and UV/VIS spectroelectrochemistry.
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.
Redox Properties of Metalloporphyrin Excited States, Lifetimes, and Related Properties of a Series of Para-Substituted Tetraphenylporphine Carbonyl Complexes of Ruthenium(II)
Rillema, D. P.,Nagle, J. K.,Barringer, L. F.,Meyer, T. J.
, p. 56 - 63 (2007/10/02)
Excited-state and redox properties of Ru(p-XTPP)(CO), X = MeO, Me, H, F, Cl, H, and Br, have been defined.Emission bands were centered at 730 +/- 3 nm and excited-state lifetimes were in the range of 30 +/- 10 μs.Two one-electron oxidations in CH2Cl2 ranged from 0.74 to 0.86 V for the first step and from 1.18 to 1.27 V for the second one.A one-electron reduction process in (CH3)2SO ranged from -1.35 to -1,24 V.Excited-state lifetimes and redox potentials exhibit a weak dependence on the Hammet ?p function.In general, redox potentials increase as the electron-withdraving power of the substituents increases, whereas excited-state lifetimes decrease.The first oxidation step (0.74-0.86 V) and the reduction step are, respectively, assigned to ?-electron removal or acceptance by porphyrin ring.The second oxidation is assigned to removal of an electrone from the ruthenium(II) center.The excited state is shown to be T(?-?*) state of porphyrin ring and to exhibit photoredox behavior involving both oxidative and reductive quenching.Redox product separation occured in flash photolysis quenching experiments and back-reactions took place at near-diffusion-controlled rates.The redox potential of the Ru(TPP)(CO)+/* couple was estimated from emission and redox data to be -0.57 +/- 0.03 V; it was determined from oxidative quenching studies to be -0.56 +/- 0.10 V.Comparison to the excited-state properties of Ru(bpy)32+ is made, and the utility of porphyrin complexes as potential solar energy storage catalysts is examined.
