12321-08-3Relevant academic research and scientific papers
A Comparative Study of Structurally Related Homogeneous Ruthenium and Iron Catalysts for the Hydrogenation of Levulinic Acid to γ-Valerolactone
van Slagmaat, Christian A. M. R.,De Wildeman, Stefaan M. A.
, p. 694 - 702 (2018)
The conversion of levulinic acid (LA) to γ-valerolactone (GVL) was investigated by employing the homogeneous Shvo catalyst (Ru-1) and iron Kn?lker-type catalysts, in order to evaluate the possibility to replace ruthenium with cheap, earth-abundant iron for this catalytic reaction. While the ruthenium-catalyzed reactions readily proceed, the activating agent required for the iron complex was found to interfere with the LA. This problem could be circumvented by pre-activating the original Kn?lker complex (Fe-1) into the corresponding dicarbonyl mono-acetonitrile iron species (Fe-3). The pre-activated iron catalyst deactivated after a few turn-overs in transfer hydrogenation reactions with isopropyl alcohol; however, highly improved GVL yields were achieved under H2 pressure to a notable maximum of 570 turn-overs for Fe-3. Nevertheless, comparative screening experiments with various solvents and kinetic studies showed that Ru-1 is still superior over Fe-3 in terms of catalytic activity.
Phosphine-free ruthenium complex-catalyzed synthesis of mono- Or dialkylated acyl hydrazides via the borrowing hydrogen strategy
Joly, Nicolas,Bettoni, Léo,Gaillard, Sylvain,Poater, Albert,Renaud, Jean-Luc
, p. 6813 - 6825 (2021/05/29)
Herein, we report a diaminocyclopentadienone ruthenium tricarbonyl complex-catalyzed synthesis of mono- or dialkylated acyl hydrazide compounds using the borrowing hydrogen strategy in the presence of various substituted primary and secondary alcohols as alkylating reagents. Deuterium labeling experiments confirm that the alcohols were the hydride source in this cascade process. Density functional theory (DFT) calculations unveil the origin and the threshold between the mono- and dialkylation.
Ruthenium-Catalyzed Three-Component Alkylation: A Tandem Approach to the Synthesis of Nonsymmetric N,N-Dialkyl Acyl Hydrazides with Alcohols
Bettoni, Léo,Joly, Nicolas,Lohier, Jean-Fran?ois,Gaillard, Sylvain,Poater, Albert,Renaud, Jean-Luc
supporting information, p. 4009 - 4017 (2021/07/02)
The borrowing hydrogen strategy has been applied in the synthesis of nonsymmetric N,N-dialkylated acyl hydrazides via a tandem three-component reaction catalyzed by a phosphine free diaminocyclopentadienone ruthenium tricarbonyl complex. This strategy represents the first direct one-pot approach to nonsymmetric functionalized acyl hydrazides. Different aromatic acyl hydrazides underwent dialkylation with a variety of primary or secondary alcohols and methanol or ethanol as alkylating agents in mild reaction conditions and good yields. Deuterium labelling experiments suggested that the primary or secondary alcohol was the hydrogen source in this tandem process. DFT calculations show that the combination of the tandem mixed product cannot be perfectly explained neither structurally nor electronically, but might be dependent of the physical state of the aldehyde or ketone intermediate (gaz vs. liquid) at the reaction temperature. (Figure presented.).
Solvent-free hydrogenation of levulinic acid to γ-valerolactone using a Shvo catalyst precursor: Optimization, thermodynamic insights, and life cycle assessment
Bernaerts, Katrien V.,De Wildeman, Stefaan M. A.,Delgove, Marie A. F.,Morick, Lukas,Stouten, Jules,Van Der Meer, Yvonne,Van Slagmaat, Christian A. M. R.
supporting information, p. 2443 - 2458 (2020/05/13)
The hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) using the η4-(2,3,4,5-tetraphenylcyclopentadienone) ruthenium tricarbonyl precursor of the well-known Shvo catalyst and H2 pressure was established under solvent-free conditions to achieve 100% conversion and 100% selectivity within 5 hours. Kinetic reaction curves were measured in order to deduce the optimal reaction conditions, which were further evaluated by means of density functional theory (DFT) calculations, and compared with catalytic concepts that consume formic acid or isopropyl alcohol as hydrogen donor. Ultimately, this alternative reaction procedure was subjected to a life cycle assessment (LCA) in comparison with the transfer hydrogenation methodologies, in order to verify its contribution towards a practice of environmentally benign chemistry.
Tandem hydroformylation/hydrogenation of alkenes to normal alcohols using Rh/Ru dual catalyst or Ru single component catalyst
Takahashi, Kohei,Yamashita, Makoto,Nozaki, Kyoko
supporting information, p. 18746 - 18757 (2013/01/15)
The catalyst system for tandem hydroformylation/hydrogenation of terminal alkenes to the corresponding homologated normal alcohol was developed. The reaction mechanism for the Rh/Ru dual catalyst was investigated by real-time IR monitoring experiments and 31P NMR spectroscopy, which proved the mutual orthogonality of Rh-catalyzed hydroformylation and Ru-catalyzed hydrogenation. Detailed investigation about Ru-catalyzed hydrogenation of undecanal under H2/CO pressure clarified different kinetics from the hydrogenation under H2 and gave a clue to design more active hydrogenation catalysts under H2/CO atmosphere. The solely Ru-catalyzed normal selective hydroformylation/hydrogenation is also reported.
Ruthenium- and enzyme-catalyzed dynamic kinetic resolution of secondary alcohols
Persson, B. Anders,Larsson, Anna L. E.,Le Ray, Mika?l,B?ckvall, Jan-E.
, p. 1645 - 1650 (2007/10/03)
Enzymatic resolution of secondary alcohols under substrate racemizing conditions was studied using an immobilized lipase from Candida antarctica in the presence of a ruthenium catalyst. A specifically designed acyl donor, 4- chlorophenyl acetate, was found to be compatible with both catalysts and resulted in an efficient dynamic kinetic resolution. Studies of the reaction in different solvents showed that nonpolar solvents gave the best results. With this process, a variety of racemic secondary alcohols were transformed to the corresponding enantiomerically pure acetates, making efficient use of all starting material. In most cases, the reaction proceeded with >99% ee and in good yield.
X-ray structure, reactivity, and catalytic properties of a (cyclopentadienone)ruthenium dimer, [(C4Ph4CO)(CO)2Ru]2
Mays, Martin J.,Morris, Michael J.,Raithby, Paul R.,Shvo, Youval,Czarkie, Dorotha
, p. 1162 - 1167 (2008/10/08)
The title complex 4a as well as several other isostructural complexes have been prepared. Single-crystal X-ray diffraction analysis of 4a indicates a centrosymmetric dimeric structure (Figure 1); the complex crystallizes in space group P1 (No. 2): a = 10.938 (1) ?, b = 11.990 (1) ?, c = 12.528 (1) ?, α = 68.62 (1)°, β = 77.99 (1)°, γ = 64.18 (1)°, V = 1374.8 (2) ?3, Z = 2 (monomer units), 4835 unique reflections, R = 0.056, 4324 reflections, F > 4σ(F). The cyclopentadienone carbonyl is bent back from the diene plane at an angle of 6.7°, with a >C=O bond length of 1.270 (7) ?. A crossover experiment with two structurally different dimer complexes indicates that the thermal dissociation of these dimers is a relatively low-energy process. Nucleophilic ligands, L (L = CO, phosphines, amines), react readily with 4a to give mononuclear complexes of the type (η4-C4Ph4CO)Ru(CO)2L. Treatment of 4a with either dihydrogen or ethanol leads to oxidative addition of dihydrogen to Ru with the formation of (η5-C4Ph4COH)(CO)2RuH. The catalytic activity of 4a and other related complexes is discussed in the light of the above results.
Catalytic reduction of nitroaromatics with carbon monoxide and water using tricarbonyltetraphenylcyclopentadienone ruthenium(0)
Shvo, Youval,Czarkie, Dorotha
, p. 357 - 366 (2007/10/02)
The complex (η4-Ph4C4C=O)(CO)3Ru (1) is a catalyst precursor in the reduction reaction of nitroarenes to anilines by CO and H2O.Azoxybenzenes and azobenzenes are by-products formed in variable quantities depending on the reaction conditions and the nature of the nitroarene used.Analysis of the reaction solution in the reaction involving nitrobenzene has revealed the presence of several complexes, including (η4-Ph4C4C=O)(CO)2Ru(H2NPh) (5), which was prepared independently; The behaviour of 5 under catalysis conditions was studied.Complex 1 did not catalyze hydrogenation of nitrobenzene.A multi-step catalytic reduction scheme is pr posed.
