123-76-2Relevant articles and documents
HReO4 as highly efficient and selective catalyst for the conversion of carbohydrates into value added chemicals
Bernardo, Joana R.,Oliveira, M. Concei??o,Fernandes, Ana C.
, p. 87 - 94 (2019)
This work describes the first catalyst (HReO4) that promotes the efficient and selective conversion of several carbohydrates into four compounds, ethyl levulinate (EL), 5-ethoxymethylfurfural (EMF), 5-hydroxymethylfurfural (HMF) and levulinic acid (LA), through a one-pot reaction strategy adjusting the reaction conditions. The reaction of fructose in ethanol at 160 °C gave EL in 80% yield after 16 h and in a mixture of ethanol/THF at 140 °C produced EMF in 73% yield after 1 h. HMF and LA can also be obtained selectively with 100% yield from fructose at 140 °C after 1 h, in DMSO or 1,4-dioxane, respectively. EL, HMF, LA and EMF were also produced in moderate to good yields from other carbohydrates such as inulin and sucrose. The catalyst HReO4 can be used in gram scale for the production of EL, EMF, HMF and LA with good yields and in at least 8 catalytic cycles on the conversion of fructose into EL with no significant reduction in its activity.
Direct production of levulinic acid in high yield from cellulose: Joint effect of high ion strength and microwave field
Qin, Kai,Yan, Yani,Zhang, Yahong,Tang, Yi
, p. 39131 - 39136 (2016)
Cellulose without any pretreatment was directly converted into levulinic acid (LA) in a microwave-assisted acidic catalytic system with a high ionic strength. The highest LA yield could reach 67.3 mol% within 60 min even when the cellulose concentration was as high as 10 wt%. It is concluded that high ion strength and microwave irradiation were jointly responsible for the fast cellulose conversion and high LA yield, and a cooperative acceleration mechanism is finally proposed. The high ion concentration provided by alkali metal halides not only accelerated the cellulose hydrolysis but also facilitated glucose conversion into LA by shifting the weak acid ionization equilibria, and microwave irradiation further promoted this salt effect by its characteristic heating way of ion conduction. Such a one-pot catalytic system provides a possibility of practical application for direct highly efficient conversion of cellulose due to its green properties, low cost and efficient characteristics.
Dauben,Thiessen,Resnick
, p. 2015 (1962)
Selective and recyclable depolymerization of cellulose to levulinicacid catalyzed by acidic ionic liquid
Ren, Huifang,Girisuta, Buana,Zhou, Yonggui,Liu, Li
, p. 569 - 576 (2015)
Cellulose depolymerization to levulinic acid (LA) was catalyzed by acidic ionic liquids (ILs) selectively and recyclably under hydrothermal conditions. The effects of reaction temperature, time, water amount and cellulose intake were investigated. Dilution effect becomes more pronounced at lower cellulose intake, dramatically improving the yield of LA to 86.1%. A kinetic model has been developed based on experimental data, whereby a good fit was obtained and kinetic parameters were derived. The relationships between IL structure, polymeric structure and depolymerization efficiency were established, shedding light on the in-depth catalytic mechanism of IL, inclusive of acidity and hydrogen bonding ability. The LA product can be readily separated through extraction by methyl isobutyl ketone (MIBK) and IL can be reused over five cycles without loss of activity. This environmentally friendly methodology can be applied to selective production of LA from versatile biomass feedstocks, including cellulose and derivatives, glucose, fructose and HMF.
High conversion of glucose to 5-hydroxymethylfurfural using hydrochloric acid as a catalyst and sodium chloride as a promoter in a water/γ-valerolactone system
Li, Minghao,Li, Wenzhi,Lu, Yijuan,Jameel, Hasan,Chang, Hou-Min,Ma, Longlong
, p. 14330 - 14336 (2017)
Biomass derived 5-hydroxymethylfurfural (HMF) is regarded as an important platform molecule for the synthesis of value-added chemicals and fuels, but the high production cost has always been a bottleneck for the industrial scale use of HMF. Different mineral acids (HCl and H2SO4) being used as the catalyst and different salts being used as the reaction promoter were evaluated. It was found that HCl, in combination with NaCl, in a water/γ-valerolactone system showed high selectivity and impressive efficiency for the synthesis of HMF from glucose. The optimal conditions to obtain the best HMF yield (62.45%) were 0.2 M HCl and 0.1 M NaCl at 140 °C with a residence time of 60 minutes. An 18.22% molar yield of LA was obtained as a by-product. The effect of different anions was also investigated, and it was determined that not only the hydrogen ions, but also the nature of the acid and the type of salt played a joint role in improving the HMF yield. In addition, a possible synthesis pathway was proposed for large scale production of HMF.
An integrated effluent free process for the production of 5-hydroxymethyl furfural (HMF), levulinic acid (LA) and KNS-ML from aqueous seaweed extract
Adimurthy, S.,Gangapur, Doddabhimappa R.,Kholiya, Faisal,Meena, Ramavatar,Rathod, Meena R.
, (2020)
This paper demonstrates an integrated zero liquid discharge (ZLD) process for time-dependent recovery of 5-hydroxymethyl furfural (HMF), levulinic acid (LA) and potassium, nitrogen and sulphur rich mother liquor (KNS-ML) - manure from agar/agarose contain
Design of Br?nsted acidic ionic liquid functionalized mesoporous organosilica nanospheres for efficient synthesis of ethyl levulinate and levulinic acid from 5-hydroxymethylfurfural
Song, Daiyu,Liu, Jingyu,Zhang, Chaoyue,Guo, Yihang
, p. 1827 - 1842 (2021)
Br?nsted acidic ionic liquids (BAILs) have brought new vitality in catalytic transformation of biomass to fuels and chemicals, but practical applications of BAILs suffer from drawbacks of slow diffusion and difficulty in separation. Chemical immobilization of BAILs is an effective way to circumvent these problems. Here, we demonstrate a series of monodispersed mesoporous organosilica nanosphere-immobilized BAIL catalysts, [C3PrIm][OTf]-MONSs (C3=PrSO3H, OTf = SO3CF3), by a quaternary ammonium surfactant micelle-directed liquid-interface assembly strategy followed by successive chemical modifications, and the particle size (180-360 nm) and pore morphology (periodic centrally radialized and 3D interconnected mesopores) of the catalysts are well-adjusted by changing the cations and/or anions of the surfactants as well as the preparation conditions. As-prepared [C3PrIm][OTf]-MONSs serve as nanoreactors to transform an important biomass-derived platform molecule, 5-hydroxymethylfurfural, in ethanol and water media to valuable chemicals, ethyl levulinate (EL) and levulinic acid (LA). By the combination of their superstrong Br?nsted acidic nature, outstanding open mesoporous spherical nanostructures and excellent textural properties, the [C3PrIm][OTf]-MONSs exhibit high ethanolysis and hydrolysis activity and selectivity. The particle size and pore morphology of the catalysts significantly influence the selectivity and thereby the yield of the products. The cetyltrimethylammonium tosylate-directed [C3PrIm][OTf]-MONSs catalyst with the smallest particle size (210 nm) and a wormhole-like interconnected mesostructure shows the highest yield of EL (93.6%) and LA (72.8%) under the optimum reaction conditions. The catalyst also displays good reusability in ethanolysis reaction, originating from chemical bonding [C3PrIm][OTf] within the hydrophobic silica framework.
ON THE QUESTION OF CARBONYL OXIDE INTERMEDIATES IN THE OXYGEN TRANSFER BY FURAN ENDOPEROXIDES AND BICYCLIC OZONIDES: INTRAMOLECULAR TRAPPING EXPERIMENTS
Adam, Waldemar,Rodriguez, Augusto
, p. 3509 - 3512 (1981)
On heating the furan endoperoxide (2) rearranges into the enol ester (4) and the bicyclic ozonide (3) affords instead the rearranged ozonide (7).The process (2)->(4) represents an intramolecular Baeyer-Villiger rearrangement presumably via the dioxirane (D-2), while the process (3)->(7) represents intramolecular trapping of the carbonyl oxide (C-3).
Comprehensive Understanding of the Role of Br?nsted and Lewis Acid Sites in Glucose Conversion into 5-Hydromethylfurfural
Li, Xiangcheng,Peng, Kaihao,Liu, Xiaohui,Xia, Qineng,Wang, Yanqin
, p. 2739 - 2746 (2017)
The conversion of glucose and selectivity into 5-hydromethylfurfural (HMF) were investigated over various silica–alumina composite (AlSiO) catalysts. The type, amount, and strength of the acidic sites were characterized by using NH3 temperature-programmed desorption and FTIR spectroscopy and then correlated to the catalytic conversion of glucose into HMF to provide a quantitative relationship between the acidity and product selectivity. Lewis acid sites played an important role in glucose conversion, which can enhance the isomerization of glucose to fructose, whereas Br?nsted acid sites had a detrimental effect. HMF selectivity had an almost linear relationship with the weak/total Lewis acid ratio (L*/L), indicating that weak Lewis acids could promote formation of HMF. The medium-to-strong Lewis acid sites can enhance the formation of undesired byproducts (levulinic acid, humins). The Br?nsted to Lewis acid ratio (B/L) had an influence on the HMF selectivity; at similar L*/L ratios, volcano curves were obtained with the increase of the B/L ratio, but the influence was not as great as that of the L*/L ratio. Nb-doped AlSiO catalysts were prepared and used in the conversion of glucose into HMF, which also confirmed the above findings. Under the optimized conditions, the HMF selectivity can reach 71 % at 92.6 % conversion of glucose with no clear decline after four catalytic cycles.
Catalytic conversion of glucose into levulinic acid using 2-phenyl-2-imidazoline based ionic liquid catalyst
Kumar, Komal,Kumar, Mukesh,Upadhyayula, Sreedevi
, (2021)
Levulinic acid (LA) is an industrially important product that can be catalytically valorized into important value-added chemicals. In this study, hydrothermal conversion of glucose into levulinic acid was attempted using Br?nsted acidic ionic liquid catalyst synthesized using 2phenyl-2-imidazoline, and 2-phenyl-2-imidazoline-based ionic liquid catalyst used in this study was synthesized in the laboratory using different anions (NO3, H2 PO4, and Cl) and characterized using1 H NMR, TGA, and FT-IR spectroscopic techniques. The activity trend of the Br?nsted acidic ionic liquid catalysts synthesized in the laboratory was found in the following order: [C4 SO3 HPhim][Cl] > [C4 SO3 HPhim][NO3 ] > [C4 SO3 HPhim][H2 PO4 ]. A maximum 63% yield of the levulinic acid was obtained with 98% glucose conversion at 180? C and 3 h reaction time using [C4 SO3 HPhim][Cl] ionic liquid catalyst. The effect of different reaction conditions such as reaction time, temperature, ionic liquid catalyst structures, catalyst amount, and solvents on the LA yield were investigated. Reusability of [C4 SO3 HPhim][Cl] catalyst up to four cycles was observed. This study demonstrates the potential of the 2-phenyl-2-imidazoline-based ionic liquid for the conversion of glucose into the important platform chemical levulinic acid.
High yield production of 5-hydroxymethylfurfural from cellulose by high concentration of sulfates in biphasic system
Shi, Ning,Liu, Qiying,Zhang, Qi,Wang, Tiejun,Ma, Longlong
, p. 1967 - 1974 (2013)
A high 5-hydroxymethylfurfural (HMF) yield of 53 mol% was obtained by direct degradation of cellulose in a biphasic system with concentrated NaHSO4 and ZnSO4 as co-catalysts, with 96% of cellulose conversion in 60 min. The high concentration of catalysts in the aqueous solution and the high volume ratio of organic phase to aqueous phase were responsible for the excellent performance. The depolymerization of cellulose is the rate-determine step, and the formed glucose could be efficiently converted by concentrated catalysts in the aqueous solution, leading to low concentration of glucose in the solution and thus suppressing the side reactions such as humin and char formation.
Selective dehydration of glucose to hydroxymethylfurfural and a one-pot synthesis of a 4-acetylbutyrolactone from glucose and trioxane in solutions of aluminium salts
Tyrlik, Stanislaw K.,Szerszen, Dorota,Olejnik, Marian,Danikiewicz, Witold
, p. 268 - 272 (1999)
Saturated water solutions of Al2(SO4)3 and AlCl3 were applied as solvent/matrices for dehydration of Glc to hydroxymethylfurfural (HMF). Addition of oxygen ligands: methanol, ethanol, THF, furan, dibutyl ether, ethyl orthoformate and trioxane influenced the yield and selectivity, the best being observed with ethanol. When Glc and trioxane were present together in reacting solution, formation of a 4-acetylbutyrolactone was observed. Copyright (C) 1999 Elsevier Science Ltd.
Selective production of levulinic acid from furfuryl alcohol in THF solvent systems over H-ZSM-5
Mellmer, Max A.,Gallo, Jean Marcel R.,Martin Alonso, David,Dumesic, James A.
, p. 3354 - 3359 (2015)
Furfuryl alcohol in high concentrations (1 M) was hydrolyzed to levulinic acid in high yields (>70%) using H-ZSM-5 zeolite as the catalyst in monophasic tetrahydrofuran (THF)-water solvent systems. Reaction kinetics studies using H-ZSM-5 were carried out, and combined with results obtained for other Br?nsted acid catalysts, we suggest that the structural properties of H-ZSM-5, in conjunction with increased reaction performance using the polar aprotic solvent THF, are effective for furfuryl alcohol hydrolysis to levulinic acid while inhibiting furfuryl alcohol polymerization reactions. In addition, on the basis of results obtained for a wide range of THF-H2O solvent systems (19:1-1:2 w/w), we suggest that the hydrophobic nature of H-ZSM-5 alters the internal solvent microenvironment within the zeolite framework, allowing for high levulinic acid yields, even at low THF solvent concentrations (e.g., 1:2 THF-H2O w/w).
Kobayashi,Akiyoshi
, (1963)
Catalytic air oxidation of biomass-derived carbohydrates to formic acid
Li, Jiang,Ding, Dao-Jun,Deng, Li,Guo, Qing-Xiang,Fu, Yao
, p. 1313 - 1318 (2012)
An efficient catalytic system for biomass oxidation to form formic acid was developed. The conversion of glucose to formic acid can reach up to 52 % yield within 3 h when catalyzed by 5 mol % of H5PV2Mo 10O40 at only 373 K using air as the oxidant. Furthermore, the heteropolyacid can be used as a bifunctional catalyst in the conversion of cellulose to formic acid (yield=35 %) with air as the oxidant. Copyright
Kinetics and reaction engineering of levulinic acid production from aqueous glucose solutions
Weingarten, Ronen,Cho, Joungmo,Xing, Rong,Conner, William Curtis,Huber, George W.
, p. 1280 - 1290 (2012)
We have developed a kinetic model for aqueous-phase production of levulinic acid from glucose using a homogeneous acid catalyst. The proposed model shows a good fit with experimental data collected in this study in a batch reactor. The model was also fitted to steady-state data obtained in a plug flow reactor (PFR) and a continuously stirred tank reactor (CSTR). The kinetic model consists of four key steps: (1) glucose dehydration to form 5-hydroxymethylfurfural (HMF); (2) glucose reversion/degradation reactions to produce humins (highly polymerized insoluble carbonaceous species); (3) HMF rehydration to form levulinic acid and formic acid; and (4) HMF degradation to form humins. We use our model to predict the optimal reactor design and operating conditions for HMF and levulinic acid production in a continuous reactor system. Higher temperatures (180-200 °C) and shorter reaction times (less than 1 min) are essential to maximize the HMF content. In contrast, relatively low temperatures (140-160 °C) and longer residence times (above 100 min) are essential for maximum levulinic acid yield. We estimate that a maximum HMF carbon yield of 14 % can be obtained in a PFR at 200 °C and a reaction time of 10 s. Levulinic acid can be produced at 57 % carbon yield (68 % of the theoretical yield) in a PFR at 149 °C and a residence time of 500 min. A system of two consecutive PFR reactors shows a higher performance than a PFR and CSTR combination. However, compared to a single PFR, there is no distinct advantage to implement a system of two consecutive reactors. Copyright
Assessment of ion exchange resins as catalysts for the direct transformation of fructose into butyl levulinate
Ramírez, Eliana,Bringué, Roger,Fité, Carles,Iborra, Montserrat,Tejero, Javier,Cunill, Fidel
, (2021)
The transformation of fructose into butyl levulinate in aqueous 1-butanol (initial molar ratio 1-butanol/fructose 79, and butanol/water 1.19) has been studied in a discontinuous reactor at 80?120 °C and 2.0 MPa over 8 sulfonic polystyrene-DVB ion exchange resins as catalysts (catalyst loading 0.85–3.4 %). Resins swell greatly in the reaction medium and the reaction takes place mainly in the swollen gel-phase. Swollen resins in water have been characterized by analysis of ISEC data, and spaces originated in the gel phase upon swelling are described in terms of zones of different polymer density. A relationship has been found between the morphology of swollen resins and ester production. Swollen resins with low polymer density show the highest butyl levulinate yield. Dowex 50Wx2 was the most effective because it creates the largest and widest spaces in the gel-phase when swelling. Consequently, it better accommodates the proton-transfer-reaction mechanisms.
Conversion of cellulose to glucose and levulinic acid via solid-supported acid catalysis
Hegner, Jessica,Pereira, Kyle C.,DeBoef, Brenton,Lucht, Brett L.
, p. 2356 - 2358 (2010)
Cellulose is hydrolyzed to glucose, which is further converted to levulinic acid in the presence of surface-supported Br?nsted and Lewis acid catalysts. Nafion catalysts, in particular, have the potential to be recycled or applied to a continuous flow reactor for the synthesis of these biofuel precursors.
Formation of C-C bonds for the production of bio-alkanes under mild conditions
Xin, Jiayu,Zhang, Suojiang,Yan, Dongxia,Ayodele, Olubunmi,Lu, Xingmei,Wang, Jianji
, p. 3589 - 3595 (2014)
It is of crucial importance to form C-C bonds between biomass-derived compounds for the production of bio-alkanes from biomass. In this study, it was found that C-C bonds can be formed between angelica lactones, key intermediates derived from biomass, through free radical reactions under mild conditions without using a noble catalyst or solvent, which gave elongated carbon chains of di/trimers with 10 or 15 carbons, with complete conversion and 100% selectivity. The di/trimers produced serve as a novel feedstock for the carbon backbones of bio-alkanes. Hydrogenation of the di/trimers produced C6-C13 hydrocarbons suitable for use as transportation fuels. This journal is the Partner Organisations 2014.
Sulfonated polyaniline as a solid organocatalyst for dehydration of fructose into 5-hydroxymethylfurfural
Dai, Jinhang,Zhu, Liangfang,Tang, Dianyong,Fu, Xing,Tang, Jinqiang,Guo, Xiawei,Hu, Changwei
, p. 1932 - 1939 (2017)
The rehydration of 5-hydroxymethylfurfural (HMF), an important bio-based chemical building block, to levulinic acid (LA) and formic acid (FA) over Br?nsted acid catalysts is the key block to the effective production of HMF from hexose. In this work, we develop a novel acidic solid organocatalyst, sulfonated polyaniline (SPAN), for the effective dehydration of fructose into HMF in the low-boiling water/1,4-dioxane cosolvent. The highest HMF yield of 71% is obtained from fructose with complete restriction of HMF rehydration to LA. We demonstrate that hydrogen bonds form between the ring-attached sulfonic acid group and the quinoid imine nitrogen as a result of internal doping, which confines the Br?nsted acidity of the SPAN catalyst. The H-bonded sulfonic acid species is active for fructose-to-HMF dehydration and complete suppression on HMF rehydration. The chemical bonding of sulfonic acid groups on the backbone of the PAN chain allows stable recyclability of the polymer catalyst. This work highlights the potential importance of confining Br?nsted acidity on a solid organocatalyst via H-bonding for transforming renewable carbohydrates into fine chemicals.
Importance of the synergistic effects between cobalt sulfate and tetrahydrofuran for selective production of 5-hydroxymethylfurfural from carbohydrates
Dong, Dehua,Hu, Xun,Li, Qingyin,Li, Xueli,Shao, Yuewen,Sun, Kai,Wang, Yi,Ye, Zhengmao,Zhang, Lijun,Zhang, Shu
, p. 2293 - 2302 (2020)
In this study, an effective catalytic system (CoSO4·7H2O/THF) for selective conversion of fructose to 5-hydroxymethylfurfural (HMF; yield: 88%) was developed. The synergistic effects among Co2+, SO42-, crystal water and tetrahydrofuran (THF) were crucial for achieving selective dehydration of fructose to HMF. Co2+ worked as a Lewis acid for catalyzing mainly dehydration of fructose to HMF but not the further decomposition of HMF to levulinic acid. THF could help to retain HMF while CoSO4 could coordinate with HMF, enhancing the thermal stability of HMF in THF. The crystal water in cobalt sulfate could help to coordinate with fructose, which facilitated the conversion of fructose via dehydration reactions. The CoSO4·7H2O/THF catalytic system could also catalyze the conversion of inulin and cellulose into HMF. The main advantages of the CoSO4·7H2O/THF catalytic system are the low cost, the easy recycling of the CoSO4·7H2O catalyst and the easy separation of HMF from volatile THF.
Effects of water and alcohols on the polymerization of furan during its acid-catalyzed conversion into benzofuran
Hu, Xun,Jiang, Shengjuan,Kadarwati, Sri,Dong, Dehua,Li, Chun-Zhu
, p. 40489 - 40501 (2016)
Furan, an important product from catalytic pyrolysis of biomass, has the potential to be further converted into value-added chemicals or biofuels. This study investigated the conversion of furan into benzofuran over a Br?nsted acid catalyst (Amberlyst 70) at 140-190°C in various solvents. With water as the solvent, furan could barely make its way to benzofuran as its polymerization dominated. With methanol as the solvent, the polymerization of furan was suppressed and benzofuran formation was enhanced substantially. This is because in methanol, the reactive intermediates (i.e., aldehydes) were stabilized and their involvement in polymerization reactions was suppressed. Other alcohols showed similar effects on suppressing polymerization. In dimethyl sulfoxide (DMSO), the polymerization of furan was also effectively suppressed. However, furan was not converted to benzofuran but to levulinic acid via a distinct reaction route.
Insights into the interplay of lewis and Br?nsted acid catalysts in glucose and fructose conversion to 5-(hydroxymethyl)furfural and levulinic acid in aqueous media
Choudhary, Vinit,Mushrif, Samir H.,Ho, Christopher,Anderko, Andrzej,Nikolakis, Vladimiros,Marinkovic, Nebojsa S.,Frenkel, Anatoly I.,Sandler, Stanley I.,Vlachos, Dionisios G.
, p. 3997 - 4006 (2013)
5-(Hydroxymethyl)furfural (HMF) and levulinic acid production from glucose in a cascade of reactions using a Lewis acid (CrCl3) catalyst together with a Br?nsted acid (HCl) catalyst in aqueous media is investigated. It is shown that CrCl3 is an active Lewis acid catalyst in glucose isomerization to fructose, and the combined Lewis and Br?nsted acid catalysts perform the isomerization and dehydration/rehydration reactions. A CrCl3 speciation model in conjunction with kinetics results indicates that the hydrolyzed Cr(III) complex [Cr(H2O)5OH]2+ is the most active Cr species in glucose isomerization and probably acts as a Lewis acid-Br?nsted base bifunctional site. Extended X-ray absorption fine structure spectroscopy and Car-Parrinello molecular dynamics simulations indicate a strong interaction between the Cr cation and the glucose molecule whereby some water molecules are displaced from the first coordination sphere of Cr by the glucose to enable ring-opening and isomerization of glucose. Additionally, complex interactions between the two catalysts are revealed: Br?nsted acidity retards aldose-to-ketose isomerization by decreasing the equilibrium concentration of [Cr(H2O)5OH]2+. In contrast, Lewis acidity increases the overall rate of consumption of fructose and HMF compared to Br?nsted acid catalysis by promoting side reactions. Even in the absence of HCl, hydrolysis of Cr(III) decreases the solution pH, and this intrinsic Br?nsted acidity drives the dehydration and rehydration reactions. Yields of 46% levulinic acid in a single phase and 59% HMF in a biphasic system have been achieved at moderate temperatures by combining CrCl3 and HCl.
Cellulose conversion to biofuel precursors using conjugated ionic liquid catalyst: An experimental and DFT study?
Kashyap, Hemant K.,Khatri, Vikas,Kumar, Komal,Upadhyayula, Sreedevi
, (2021)
In this study, an efficient catalytic system has been developed for the single step conversion of microcrystalline cellulose into 5-hydroxymethyl furfural and levulinic acid using Br?nsted acidic ionic liquid (IL) catalysts which have large conjugated structure. The IL catalysts used in this study comprising of different anions ([CF3SO3]?, [HSO4]?, [CF3COO]?, and [Cl]?) with a common cation 1-butyl sulfonic acid-2-phenylimidazolinium ([2-PhIm-SO3H]+), were synthesized in laboratory and characterized. The MCC conversion was carried out in a biphasic reaction medium and yields of 70 % for 5-HMF and 23 % for LA were achieved at 150 °C and 5 h reaction time. Furthermore, density functional theory (DFT) was performed to identify the key interactions in the stable configurations of the ion-pairs of ILs. The electronic properties and chemical reactivity of the individual ions and ion-pairs of ILs were investigated by performing natural bond orbital (NBO) and second order perturbation theory analysis.
One-Pot Transformation of Cellobiose to Formic Acid and Levulinic Acid over Ionic-Liquid-based Polyoxometalate Hybrids
Li, Kaixin,Bai, Linlu,Amaniampong, Prince Nana,Jia, Xinli,Lee, Jong-Min,Yang, Yanhui
, p. 2670 - 2677 (2014)
Currently, levulinic acid (LA) and formic acid (FA) are considered as important carbohydrates for the production of value-added chemicals. Their direct production from biomass will open up a new opportunity for the transformation of biomass resource to valuable chemicals. In this study, one-pot transformation of cellobiose into LA and FA was demonstrated, using a series of multiple-functional ionic liquid-based polyoxometalate (IL-POM) hybrids as catalytic materials. These IL-POMs not only markedly promoted the production of valuable chemicals including LA, FA and monosaccharides with high selectivities, but also provided great convenience of the recovery and the reuse of the catalytic materials in an environmentally friendly manner. Cellobiose conversion of 100 %, LA selectivity of 46.3 %, and FA selectivity of 26.1 % were obtained at 423 K and 3 MPa for 3 h in presence of oxygen. A detailed catalytic mechanism for the one-pot transformation of cellobiose was also presented.
Oxidation of cyclohexanone and/or cyclohexanol catalyzed by Dawson-type polyoxometalates using hydrogen peroxide
Dermeche, Leila,Idrissou, Yasmina,Mazari, Tassadit,Moudjahed, Mohammed,Rabia, Cherifa
, (2022/03/07)
The oxidation of cyclohexanone, cyclohexanol or cyclohexanone/cyclohexanol mixture using as catalyst, Dawson-type polyoxometalates (POMs) of formula, α- and β-K6P2W18O62, α-K6P2Mo6W12O62 and α1-K7P2Mo5VW12O62 and hydrogen peroxide, carried out at 90 °C with a reaction time of 20 h, led to a high number of mono- and di-acids which were identified by GC-MS. Levulinic, 6-hydroxyhexanoic, adipic, glutaric and succinic acids, major products were evaluated by HPLC. Regardless of the substrate nature, all POMs exhibited high catalytic activity with 94–99% of conversion, whereas the formation of the different products is sensitively related to both the composition and symmetry of the POMs and the substrate nature. The main products are adipic acid in the presence of α-K6P2Mo6W12O62 and α1-K7P2Mo5VW12O62, levulinic acid in the presence of α1-K7P2Mo5VW12O62 and β-K6P2W18O62 and 6-hydroxyhexanoic acid in the presence of α- and β-K6P2W18O62. Graphical abstract: High catalytic activity was observed with?α- and?β-K6P2W18O62, α-K6P2Mo6W12O62 and α1-K7P2Mo5VW12O62 Dawson-type for the oxidation of cyclohexanone, cyclohexanol or cyclohexanone/cyclohexanol mixture, in the hydrogen peroxide presence, to several oxygenated products. Adipic, levulinic and 6-hydroxyhexanoic acids are the main products. The peroxo- species formed in situ could be the active sites.[Figure not available: see fulltext.]
Acylative Kinetic Resolution of Cyclic Hydroxamic Acids
Yin, Jingwei,Straub, Matthew R.,Liao, Julian D.,Birman, Vladimir B.
supporting information, p. 1546 - 1549 (2022/03/01)
Racemic cyclic hydroxamic acids bearing an aryl substituent adjacent to the hydroxyl group undergo effective acylative kinetic resolution promoted by benzotetramisole (BTM).
Catalytic wet air oxidation of D-glucose by perovskite type oxides (Fe, Co, Mn) for the synthesis of value-added chemicals
Geobaldo, Francesco,Pirone, Raffaele,Russo, Nunzio,Scelfo, Simone
, (2022/03/15)
The conversion of common biomasses derived, as D-glucose, into value-added chemicals has received highest attention in the last few years. Among all processes, the catalytic wet air oxidation (CWAO) of derived biomasses using noble metal-based heterogeneo
