6149-46-8Relevant articles and documents
Catalytic Transfer Hydrogenation of Ethyl Levulinate to γ-Valerolactone Over Ni Supported on Equilibrium Fluid-Catalytic-Cracking Catalysts
Chen, Han,Xu, Qiong,Li, Hui,Liu, Jian,Liu, Xianxiang,Huang, Geng,Yin, Dulin
, p. 538 - 547 (2020/07/30)
Nickel supported on equilibrium fluid-catalytic-cracking catalysts (Ni/E-cats) were prepared by a simple grinding-pyrolysis method and employed for the transfer hydrogenation of ethyl levulinate (EL) to γ-valerolactone (GVL). 96.2% selectivity of GVL and 90.3% conversion of EL were obtained at 180?°C for 6?h over 30-Ni/E-cat. Through XRD, N2 adsorption–desorption, NH3-TPD and SEM analysis, the high activity of the 30-Ni/E-cat catalyst was attributed to its dispersed Ni metal active centers and available acidic sites. Catalytic probe test revealed that metal and acid sites of Ni/E-cat played a synergistic catalytic role in the synthesis of GVL in 2-propanol, where Ni metal sites contribute to the hydrogenation of ketone group in EL, and acid sites of E-cat promoted the lactonization of intermediate ethyl- or isopropyl 4-hydroxyvalerate. Two reaction pathways and synergistic mechanism were proposed in this catalytic system. Moreover, Ni/E-cat catalyst exhibited good stability up to four cycles without obvious loss of catalytic activity. Graphic Abstract: [Figure not available: see fulltext.]
A Diaminopropane Diolefin Ru(0) Complex Catalyzes Hydrogenation and Dehydrogenation Reactions
Casas, Fernando,Trincado, Monica,Rodriguez-Lugo, Rafael,Baneerje, Dipshikha,Grützmacher, Hansj?rg
, p. 5241 - 5251 (2019/11/16)
New ruthenium (0) complexes with a cooperative diolefin diaminopropane (DAP) or the dehydrogenated iminopropenamide ligand (IPA) were synthesized for comparison with their diaminoethane (DAE)/ diazadiene (DAD) ruthenium analogues. These DAP/IPA complexes are efficient catalysts in dehydrogenation reactions of alkaline aqueous methanol which proceeds under mild conditions (T=70 °C) and of higher alcohols, forming the corresponding carbonate and carboxylates, respectively. The scope of the reaction includes an example of a 1,2-diol as model for biomass derived alcohols. Their catalytic applications are extended to the atom-efficient dehydrogenative coupling of alcohols and amines to amides. The reaction proceeds without any additives and is applicable to the synthesis of formamides from methanol. Moreover, DAP/IPA complexes catalyze the hydrogenation of a series of esters, lactone, ketone, activated olefin, aldehyde and imine substrates. The diaminopropane Ru catalyst exhibits higher activity compared to the dehydrogenated β-ketiminate (IPA) and previously studied DAD/DAE based catalysts. We present studies on their stoichiometric reactivity with relevance to their possible catalytic mechanisms and the isolation and full characterization of key reaction intermediates.
Continuous Hydrogenation of Ethyl Levulinate to 1,4-Pentanediol over 2.8Cu-3.5Fe/SBA-15 Catalyst at Low Loading: The Effect of Fe Doping
Deng, Tianyu,Yan, Long,Li, Xinglong,Fu, Yao
, p. 3837 - 3848 (2019/08/07)
Bimetallic Cu–Fe catalysts with low loading were prepared for hydrogenation of ethyl levulinate (EL) to 1,4-pentanediol (1,4-PDO). Among them, 2.8Cu-3.5Fe/SBA-15 (Cu/Fe molar ratio of 1:1.5) performed best, capable of converting EL to the key intermediate γ-valerolactone (GVL) at 140 °C with 97 % yield. It can also be used to hydrogenate GVL to 1,4-PDO with 92.6 % selectivity or convert EL to 1,4-PDO in one pot. The high activity of the catalyst at such a low loading was attributed to the highly dispersed metal species and the Fe doping effect. Various characterization methods indicated that Fe acted as both structural and electronic modifier to promote the chemical properties of the Cu species. Besides, the incorporation of Fe provided abundant Lewis acid sites and accelerated the reaction process. CuFeO2 was detected by energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and XRD. On the basis of a combination of characterization and reaction kinetics, synergistic catalysis by Cu0 and CuFeO2 is considered to be responsible for the excellent performance of the Cu–Fe catalysts.
