103712-26-1Relevant articles and documents
PREPARATION D'ALKYL-4 γ-LACTONES OPTIQUEMENT ACTIVES
Vigneron, J. P.,Bloy, V.
, p. 1735 - 1738 (1980)
Highly pure enantiomers of 4-alkyl γ-lactones are synthesized from optically active propargylic carbinols obtained by asymmetric reduction of α-acetylenic ketones with the chiral complex (LiAlH4, N-methylephedrine-3,5 dimethylphenol).
Selective hydrogenation of levulinic acid to 1,4-pentanediol in water using a hydroxyapatite-supported Pt-Mo bimetallic catalyst
Mizugaki,Nagatsu,Togo,Maeno,Mitsudome,Jitsukawa,Kaneda
, p. 5136 - 5139 (2015)
Hydroxyapatite-supported Pt-Mo bimetallic nanoparticles (Pt-Mo/HAP) catalyze the selective transformation of levulinic acid to 1,4-pentanediol under aqueous conditions. A concerted effect between Pt nanoparticles and molybdenum oxides facilely promotes the hydrogenation of the intermediates 4-hydroxypentanoic acid and γ-valerolactone to 1,4-pentanediol. The Pt-Mo/HAP catalyst is recoverable and reusable while maintaining its high activity and selectivity.
Transfer hydrogenation of levulinic acid from glycerol and ethanol using water-soluble iridium N-heterocyclic carbene complexes
Culley, Keira,Heltzel, Jacob,Lemcoff, Gabriel,Sandefur, Evan,Voutchkova-Kostal, Adelina,Wang, Kai
, (2020)
The upgrading of biomass derivatives to biofuels and chemicals through transfer hydrogenation (TH) is attractive relative to direct hydrogenation, especially when the hydrogen donors can be sourced renewably. Here we report the first process that uses glycerol, a renewable waste material from biodiesel processing, as a hydrogen donor in the catalytic TH of a biomass-derived platform chemical, levulinic acid, to selectively afford γ-hydroxyvaleric acid (GHV) and lactic acid (LA). GHV can be further converted to γ-valerolactone (GVL), a widely used platform chemical. Levulinic acid can be used directly, without esterification, which is typically needed for transfer hydrogenation. The process is efficiently facilitated by robust iridium N-heterocyclic carbene (NHC) complexes with sulfonate functional groups at low catalyst loading (1–10 ppm), affording quantitative conversion of levulinic acid in the presence of KOH to GHV, with >100,000 TON in 2 h at 150 °C, using 1 ppm catalyst. The most prolific catalyst, [(NHC-SO3-)2(CO)2Ir]Na, can also facilitate transfer hydrogenation from other hydrogen donors, such as 2-propanol, potassium formate, and most notably, ethanol, which can also be derived from renewables. Ethanol is a highly efficient hydrogen donor for levulinic acid using this catalyst, affording >7,000 turnovers in 2 h using 10 ppm catalyst.
Ir(triscarbene)-catalyzed sustainable transfer hydrogenation of levulinic acid to γ-valerolactone
Sung, Kihyuk,Lee, Mi-hyun,Cheong, Yeon-Joo,Jang, Hye-Young
, (2021)
Sustainable iridium-catalyzed transfer hydrogenation using glycerol as the hydride source was employed to convert levulinic acid to γ-valerolactone (GVL) with exceptionally high turnover numbers (TONs) (500,000) and turnover frequencies (TOFs) (170,000 h?1). The highly efficient triscarbene-modified iridium catalysts demonstrated good catalytic activities with low catalyst loadings (0.7 ppm) and good recyclability with an accumulated TON of over two million in the fourth reaction. In addition to glycerol, propylene glycol (PG), ethylene glycol (EG), isopropanol (IPA), and ethanol (EtOH) successfully transferred hydrides to levulinic acid, producing GVL with TONs of 339,000 (PG), 242,000 (EG), 334,000 (IPA), and 208,000 (EtOH), respectively. Deuterium-labeling experiments were conducted to gain insight into the reaction mechanism.
Highly Efficient Hydrogenation of Levulinic Acid into Γ-Valerolactone using an Iron Pincer Complex
Yi, Yuxuan,Liu, Huiying,Xiao, Ling-Ping,Wang, Bo,Song, Guoyong
, p. 1474 - 1478 (2018)
The search for nonprecious-metal-based catalysts for the synthesis of γ-valerolactone (GVL) through hydrogenation of levulinic acid and its derivatives in an efficient fashion is of great interest and importance, as GVL is an important a sustainable liquid. We herein report a pincer iron complex that can efficiently catalyze the hydrogenation of levulinic acid and methyl levulinate into GVL, achieving a turnover number of up to 23 000 and a turnover frequency of 1917 h?1. This iron-based catalyst also enabled the formation of GVL from various biomass-derived carbohydrates in aqueous solution, thus paving a new way toward a renewable chemical industry.
A Multiphase Protocol for Selective Hydrogenation and Reductive Amination of Levulinic Acid with Integrated Catalyst Recovery
Bellè, Alessandro,Tabanelli, Tommaso,Fiorani, Giulia,Perosa, Alvise,Cavani, Fabrizio,Selva, Maurizio
, p. 3343 - 3354 (2019)
At 60–150 °C and 15–35 bar H2, two model reactions of levulinic acid (LA), hydrogenation and reductive amination with cyclohexylamine, were explored in a multiphase system composed of an aqueous solution of reactants, a hydrocarbon, and commercial 5 % Ru/C as a heterogeneous catalyst. By tuning the relative volume of the immiscible water/hydrocarbon phases and the concentration of the aqueous solution, a quantitative conversion of LA was achieved with formation of γ-valerolactone or N-(cyclohexylmethyl)pyrrolidone in >95 and 88 % selectivity, respectively. Additionally, the catalyst could be segregated in the hydrocarbon phase and recycled in an effective semi-continuous protocol. Under such conditions, formic acid additive affected the reactivity of LA through a competitive adsorption on the catalyst surface. This effect was crucial to improve selectivity for the reductive amination process. The comparison of 5 % Ru/C with a series of carbon supports demonstrated that the segregation phenomenon in the hydrocarbon phase, never previously reported, was pH-dependent and effective for samples displaying a moderate surface acidity.
Exploring the ruthenium catalysed synthesis of γ-valerolactone in alcohols and utilisation of mild solvent-free reaction conditions
Al-Shaal, Mohammad G.,Wright, William R. H.,Palkovits, Regina
, p. 1260 - 1263 (2012)
Levulinic acid and alkyl-levulinates have been hydrogenated using a range of supported catalysts. The different reaction outcomes obtained in alternate solvents have been rationalized and the influence of varying catalyst supports examined. A range of solvent free conditions have been investigated with complete LA conversion obtained at temperatures as low as 25 °C.
Carboxyl Group-Directed Iridium-Catalyzed Enantioselective Hydrogenation of Aliphatic ?-Ketoacids
Li, Mao-Lin,Li, Yao,Li, Yi-Hao,Pan, Jia-Bin,Song, Song,Zhou, Qi-Lin,Zhu, Shou-Fei
, p. 10032 - 10039 (2020)
Although the transition metal-catalyzed asymmetric hydrogenation of aromatic ketones has been extensively explored, the enantioselective hydrogenation of aliphatic ketones remains a challenge because chiral catalysts cannot readily discriminate between the re and si faces of these ketones. Herein, we report a carboxyl-directing strategy for the asymmetric hydrogenation of aliphatic ?-ketoacids. With catalysis by iridium complexes bearing chiral spiro phosphino-oxazoline ligands, hydrogenation of aliphatic ?-ketoacids afforded chiral ?-hydroxylacids with high enantioselectivity (up to 99% ee). Mechanistic studies revealed that the carboxyl group of the substrate directs hydrogen transfer and ensures high enantioselectivity. Density functional theory calculations suggested the occurrence of chiral induction involving a hydrogen-hydrogen interaction between a hydride on the iridium atom and the substituent on the oxazoline ring of the ligand, and on the basis of the calculations, we proposed a catalytic cycle involving only Ir(III), which differs from the Ir(III)/Ir(V) catalytic cycle that operates in the hydrogenation of α,β-unsaturated carboxylic acids.
Catalytic transfer hydrogenation of biomass-derived levulinic acid to γ-valerolactone over Sn/Al-SBA-15 catalysts
Durai, Mani,Erusappan, Elangovan,Kumaravel, Sakthivel,Thiripuranthagan, Sivakumar,Vembuli, Thanigaivel
, p. 8209 - 8222 (2020)
Gamma valerolactone (GVL) is an important chemical feedstock from which several value-added fine chemicals, fuels and fuel additives are manufactured. GVL is the product obtained in the hydrogenation of levulinic acid (LA), which in turn is generally manufactured from several renewable resources such as pentoses and hexoses. The present work deals with the synthesis of SBA-15 and Sn loaded catalysts [x% Sn/Al-SBA-15 (x = Si/Sn = 10, 25, 50, 75 and 100 with Si/Al = 25)] using a hydrothermal in situ method. A variety of both bulk and surface characterization techniques such as XRD, FT-IR, BET, FE-SEM, HR-TEM, XPS, TGA/DTA and UV-DRS were used to characterize the bare and Sn/Al-SBA-15 catalysts. The characterization studies revealed the presence of Sn species well dispersed in the uniform pore channels of Al-SBA-15. All the synthesized catalysts were tested in the liquid-phase catalytic transfer hydrogenation of levulinic acid at atmospheric N2 pressure under mild reaction conditions. Among them, the Sn/Al-SBA-15 (Si/Sn = 25) catalyst showed remarkable conversion of levulinic acid (99%) and very high selectivity towards GVL (100%). The various reaction parameters such as metal loading, reaction temperature, reaction time and catalyst weight were optimized to get the maximum conversion of levulinic acid with high selectivity towards the desired product. The stability and reusability of the best catalysts were also tested up to five cycles and there was not much variation in the catalytic activity in terms of conversion.
Microwave-Assisted γ-Valerolactone Production for Biomass Lignin Extraction: A Cascade Protocol
Tabasso, Silvia,Grillo, Giorgio,Carnaroglio, Diego,Gaudino, Emanuela Calcio,Cravotto, Giancarlo
, (2016)
The general need to slow the depletion of fossil resources and reduce carbon footprints has led to tremendous effort being invested in creating "greener" industrial processes and developing alternative means to produce fuels and synthesize platform chemicals. This work aims to design a microwave-assisted cascade process for a full biomass valorisation cycle. GVL (γ-valerolactone), a renewable green solvent, has been used in aqueous acidic solution to achieve complete biomass lignin extraction. After lignin precipitation, the levulinic acid (LA)-rich organic fraction was hydrogenated, which regenerated the starting solvent for further biomass delignification. This process does not requires a purification step because GVL plays the dual role of solvent and product, while the reagent (LA) is a product of biomass delignification. In summary, this bio-refinery approach to lignin extraction is a cascade protocol in which the solvent loss is integrated into the conversion cycle, leading to simplified methods for biomass valorisation.
