98-01-1

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• Mesoporous tantalum phosphates: Preparation, acidity and catalytic performance for xylose dehydration to produce furfural
• Mesoporous tantalum phosphates (TaOPO4-m) with varying P/Ta molar ratios (m = 0.41-0.89) were prepared, comprehensively characterized by ICP-AES, N2 physisorption, small-angle XRD, TEM, Raman, FT-IR, NH3-TPD and IR of pyridine adsorption and employed to catalyze the dehydration of xylose to produce furfural in a biphasic batch reactor. The physicochemical properties of these TaOPO4-m samples were affected significantly by variation of m. More ordered mesopores were formed in the sample with a higher m. On the other hand, the density of acidity decreased but the ratio of Br?nsted acidity to Lewis acidity (B/L) increased with the increase in m. TaOPO4-0.84, which showed adequate mesoporosity and a high B/L ratio, was identified as the best performing catalyst among these TaOPO4-m catalysts in terms of high furfural selectivity (ca. 72 mol%). Correlating the catalyst performance with its acid property showed that the xylose consumption rate decreased with the increasing B/L ratio, while furfural selectivity showed a volcano-type dependence on the B/L ratio. Besides, the huge decrease in the furfural selectivity after poisoning the Br?nsted acid sites by adding 2,6-dimethyl pyridine revealed a kind of Br?nsted acid catalysis for selective furfural production.
• Xing, Yanran,Yan, Bo,Yuan, Zifei,Sun, Keqiang

• p. 59081 - 59090

  (2016)
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• Dehydration of xylose over sulfated tin oxide catalyst: Influences of the preparation conditions on the structural properties and catalytic performance
• Various sulfated metal oxides were tested as solid acid catalyst for the dehydration of xylose to furfural under milder conditions. On the basis of our findings that sulfated tin oxide exhibited the highest catalytic activity, the effects of the content of SO42- group and the calcination temperature on the structural properties and catalytic performance were investigated, and the reusability of the sulfated tin oxide catalyst was evaluated. The acid property on the sulfated tin oxide catalyst was characterized by in situ FT-IR observations of the CO-adsorbed sample. Finally, the reaction mechanism of dehydration of xylose over the SO4 2-/SnO2 catalyst was considered.
• Suzuki, Takeshi,Yokoi, Toshiyuki,Otomo, Ryoichi,Kondo, Junko N.,Tatsumi, Takashi

• p. 117 - 124

  (2011)
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• Improving Biocatalytic Synthesis of Furfuryl Alcohol by Effective Conversion of D-Xylose into Furfural with Tin-Loaded Sulfonated Carbon Nanotube in Cyclopentylmethyl Ether-Water Media
• Carbon nanotube (CNT) was utilized as as the precursor to synthesize solid acid (tin-loaded sulfonated carbon nanotube, SO42?/SnO2-CNT) for catalyzing D-xylose into furfural. Fourier transform infrared spectroscopy, Roman spectroscopy, X-ray diffraction analysis, and scanning electron microscope techniques were used for characterizing SO42?/SnO2-CNT. Different loading of D-xylose (20–100?g/L) were converted into furfural (81.6–299.1?mM) at 41.9–61.2% yield by SO42?/SnO2-CNT (3.5 wt%) within 15?min at 180 °C in cyclopentylmethyl ether-water (1:2, v:v) biphasic media. Subsequently, whole-cells of recombinant Escherichia coli CG-19 cells expressing reductase catalyzed D-xylose-derived furfural at 35 ℃ and pH 7.5. Within 3?h, the prepared D-xylose (81.6–299.1?mM) could be converted into furfuryl alcohol at 32.7–61.2% yield (based on the D-xylose loading). Sequential conversion of D-xylose with SO42?/SnO2-CNT and reductase catalysts was established for the effective production of furfuryl alcohol. Graphic Abstract: [Figure not available: see fulltext.]
• Li, Qi,Hu, Yun,Tao, Yong-You,Zhang, Peng-Qi,Ma, Cui-Luan,Zhou, Yu-Jie,He, Yu-Cai

• p. 3189 - 3196

  (2021)
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• Conversion of xylose, xylan and rice husk into furfural via betaine and formic acid mixture as novel homogeneous catalyst in biphasic system by microwave-assisted dehydration
• Dehydration of D-xylose and direct transformation of xylan into furfural were achieved by means of betaine-formic acid (HCOOH) catalytic system. All reactions were microwave-assisted and carried out in a CPME-water biphasic system. At 170?°C, in a pH range between 1.9 and 2.3, highest yields of 80% and 76% were obtained respectively for the pentose and the polysaccharide. Time dependence of the dehydration and influence of the temperature on the reaction kinetics were studied. Besides, at 190?°C, using the optimized condition of the reaction, rice husk was also employed as a source of furfural with a single stage reaction.
• Delbecq, Frederic,Wang, Yantao,Len, Christophe

• p. 520 - 525

  (2016)
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• Dehydration of D-xylose into furfural over bimetallic salts of heteropolyacid in DMSO/H2O mixture
• Dehydration of D-xylose to yield furfural was carried out using bimetallic salts of a heteropolyacid as the catalyst at 160–220 °C in the DMSO/H2O mixtures. The effect of Sn/Cs molar ratio of the bimetallic salts of 12-tungstophosphoric acid (PW) obtained by ultrasound-assisted coprecipitation on dehydration of D-xylose was investigated. The resultant catalysts were characterized by X-ray diffraction, N2 adsorption, field emission scanning electron microscopy and energy dispersive X-ray (EDX). It was found that the Sn-Cs codoped PW catalysts retained the Keggin crystal structure of PW. Sn0.625Cs0.5PW was the most active catalyst in the dehydration of D-xylose into furfural. The maximum D-xylose conversion (close to 100 wt %) and furfural yield (63 wt %) were achieved at 200 °C for 3 h in DMSO/H2O mixtures. It was found that 16.7 wt % Sn0.625Cs0.5PW on a chitosan-derived support displayed similar catalytic activity to that of Sn0.625Cs0.5PW and good stability after recycling six times.
• Guo, Xiaoqian,Guo, Feng,Li, Yishan,Zheng, Zhangqin,Xing, Zhexu,Zhu, Zihan,Liu, Ting,Zhang, Xin,Jin, Ying

• p. 18 - 25

  (2018)
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• The role of xylulose as an intermediate in xylose conversion to furfural: insights via experiments and kinetic modelling
• An experimental work has been performed to study the relevance of xylulose as an intermediate in xylose conversion to furfural in aqueous solution. The furfural formation was investigated at the temperature range from 180 to 220 °C during non-catalyzed and acid-catalyzed conversion of xylose in a stirred microwave-assisted batch reactor. The separate experiments on xylulose and furfural conversions were carried out under similar conditions. The maximum furfural yields obtained from xylose were 48 mol% and 65 mol% for the non-catalyzed and the acid-catalyzed processes, respectively. It was shown that the furfural yield is significantly lower from xylulose than from xylose. Furthermore, the effects of initial xylose concentration and the formation of xylulose were investigated in a mechanistic modeling study. A new reaction mechanism was developed taking into account the xylulose formation from xylose. Based on the experimental results and the proposed reaction model, it was concluded that xylose isomerization to xylulose with subsequent furfural formation is not a primary reaction pathway. The obtained kinetic parameters were further used for plug flow reactor simulations to evaluate furfural yields achievable by an optimized continuous operation.
• Ershova,Kanervo,Hellsten,Sixta

• p. 66727 - 66737

  (2015)
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• Furfural production in a biphasic system using a carbonaceous solid acid catalyst
• The formation of furfural from xylose was investigated under heterogeneously catalyzed conditions with Starbon450-SO3H as a catalyst in a biphasic system. Experiments were performed based on a statistical experimental design. The variables considered were time and temperature. Starbon450-SO3H was characterized by scanning electron microscopy, N2-physisorption, thermogravimetric analysis, diffuse reflectance infrared Fourier transform, Raman spectroscopy, pyridine titration and X-ray photoelectron spectroscopy. The results indicate that sulfonated Starbon450-SO3H can be an effective solid acid catalyst for furfural formation. A maximum furfural yield and selectivity of 70 mol% was achieved at complete xylose conversion under optimum experimental conditions. The present paper suggests that functionalized Starbon450-SO3H can be employed as an efficient solid acid catalyst that has significant hydrothermal stability and can be reused for several cycles to produce furfural from xylose.
• Gómez Millán, Gerardo,Phiri, Josphat,M?kel?, Mikko,Maloney, Thad,Balu, Alina M.,Pineda, Antonio,Llorca, Jordi,Sixta, Herbert

• (2019)
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• Synergy effect between solid acid catalysts and concentrated carboxylic acids solutions for efficient furfural production from xylose
• An efficient furfural formation from xylose was demonstrated combining a concentrated aqueous solution of acetic acid and solid acid catalysts. Higher furfural yields and selectivities were obtained by comparison to the catalytic performances obtained in pure water. The evident synergy effect observed at 150 °C between the aqueous carboxylic acid solution and the solid acid catalysts is tentatively explained by the occurrence of two phenomena: 1) the contribution of Lewis acid sites which would operate in cooperation with the homogeneous weak Br?nsted acidity brought by the aqueous acetic acid solution. According to the literature, the two steps mechanism involving the xylose-xylulose isomerization over Lewis acid sites and the successive Br?nsted acid catalyzed cyclodehydration to furfural would be the prevailing reaction pathway in the heterogeneous-homogenous catalytic system at 150 °C. 2) an enhancement of the surface solid acid coverage by the carbohydrate and furfural owing to the presence of carboxylic acid in the aqueous solution as shown by comparative liquid phase adsorption experiments done in pure water and in aqueous acetic acid solutions. Among a series of solid acid catalysts, ZrW, Cs2HPW12O40, HY (Si/Al = 15), K10 and NbOH, the latter one, NbOH used non-calcinated was shown to be active, selective and stable in the aqueous acetic acid media. HY and K10 are as active and selective for furfural formation but suffer for a strong Al leaching which precludes their utilization as true solid acid catalyst in acetic acid media.
• Doiseau, Aude-Claire,Rataboul, Franck,Burel, Laurence,Essayem, Nadine

• p. 176 - 184

  (2014)
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• Furfural production from xylose + glucose feedings and simultaneous N 2-stripping
• The current furfural manufacturing process is based on homogeneous catalysts as well as steam as the stripping agent. Novel xylose-dehydration research studies include heterogeneous catalysts with high acidity and tailored selectivity. This work aims to evaluate the effect of additional glucose with the xylose feeding during simultaneous N2-stripping of furfural catalyzed by ion-exchange resins. Given the low batch performance of Amberlyst 70, the N2-stripping data showed high furfural yields and selectivity in the condensate stream. The different continuous feeding configurations showed that xylose/glucose ratios similar to the real pentosan-rich biomass could be fed achieving furfural yields of 75% at 200 °C. Moreover, the proposed study serves as a preliminary study to achieve high xylose conversion and relatively low glucose dehydration rates, showing its potential as a possible future process for the upgrading of carbohydrates to furan-based fuel additives.
• Agirrezabal-Telleria,Requies,Gueemez,Arias

• p. 3132 - 3140

  (2012)
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• Efficient, stable, and reusable silicoaluminophosphate for the one-pot production of furfural from hemicellulose
• Development of stable, reusable, and water-tolerant solid acid catalysts in the conversion of polysaccharides to give value-added chemicals is vital because catalysts are prone to undergo morphological changes during the reactions. With the anticipation that silicoaluminophosphate (SAPO) catalysts will have higher hydrothermal stability, those were synthesized, characterized, and employed in a one-pot conversion of hemicellulose. SAPO-44 catalyst at 170 C within 8 h could give 63% furfural yield with 88% mass balance and showed similar activity up to at least 8 catalytic cycles. The morphological studies revealed that SAPO catalysts having hydrophilic characteristics are stable under reaction conditions.
• Bhaumik, Prasenjit,Dhepe, Paresh L.

• p. 2299 - 2303

  (2013)
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• Unveiling the role of choline chloride in furfural synthesis from highly concentrated feeds of xylose
• Furfural is a biomass derived compound used for the synthesis of fuels and chemicals. Herein we show that choline chloride allows the conversion of highly concentrated feeds of xylose (up to 50 wt%) to furfural (up to 75%) and that it can be recycled. Such a beneficial effect was observed from the formation of a choline xyloside intermediate exhibiting higher reactivity than xylose.
• Jiang,Verrier,Ahmar,Lai,Ma,Muller,Queneau,Pera-Titus,Jér?me,De Oliveira Vigier

• p. 5104 - 5110

  (2018)
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• Supported task-specific ionic liquid catalyst for highly efficient and recyclable aerobic oxidation of benzyl alcohols
• A novel catalytic system was prepared by impregnating ionic liquid immobilized 2,2,6,6-tetramethylpiperidyl-1-oxyl (TEMPO) and copper salt onto various silica supports. This catalytic system was capable of rapidly converting different benzylic and allylic alcohols into the corresponding aldehydes under O2 atmosphere with high conversion. Recycling results showed that the catalyst could be easily recovered and reused.
• Liu, Lin,Ma, Juanjuan,Sun, Zhen,Zhang, Jianping,Huang, Jingjing,Li, Shanzhong,Tong, Zhiwei

• p. 68 - 71

  (2011)
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• Suggitt et al.

• p. 373,376

  (1947)
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• High performance mesoporous zirconium phosphate for dehydration of xylose to furfural in aqueous-phase
• The conversion of sugars to chemicals in aqueous-phase is especially important for the utilization of biomass. In current work, zirconium phosphate obtained by hydrothermal methods using organic amines as templates has been examined as a solid catalyst for the dehydration reaction of xylose to furfural in aqueous-phase. The use of dodecylamine and hexadecylamine in the synthesis process results in mesoporous zirconium phosphate with uniform pore width of ～2 nm and in morphology of nanoaggregates, which is characterized by powder X-ray diffraction, N2 isothermal sorption, NH3 temperature-programmed desorption, FT-IR, and 31P MAS NMR spectroscopy. When used as a catalyst for xylose dehydration to furfural in aqueous-phase, the mesoporous zirconium phosphate presents excellent catalytic performance with high conversions up to 96% and high furfural yields up to 52% in a short time of reaction. Moreover, the catalyst is easily regenerated by thermal treatment in air and shows quite stable activity. The open structure with numerous active sites of the Bronsted/Lewis acid sites is responsible for the high catalytic efficiency of mesoporous zirconium phosphate.
• Cheng, Liyuan,Guo, Xiangke,Song, Chenhai,Yu, Guiyun,Cui, Yuming,Xue, Nianhua,Peng, Luming,Guo, Xuefeng,Ding, Weiping

• p. 23228 - 23235

  (2013)
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• Conversion of xylose into furfural using lignosulfonic acid as catalyst in ionic liquid
• Preparation of biopolymer-based catalysts for the conversion of carbohydrate polymers to new energies and chemicals is a hot topic nowadays. With the aim to develop an ecological method to convert xylose into furfural without the use of inorganic acids, a biopolymer-derived catalyst (lignosulfonic acid) was successfully used to catalyze xylose into furfural in ionic acid ([BMIM]Cl). The characteristics of lignosulfonic acid (LS) and effects of solvents, temperature, reaction time, and catalyst loading on the conversion of xylose were investigated in detail, and the reusability of the catalytic system was also studied. Results showed that 21.0% conversion could be achieved at 100 °C for 1.5 h. The method not only avoids pollution from conventional mineral acid catalysts and organic liquids but also maked full use of a byproduct (lignin) from the pulp and paper industry, thus demonstrating an environmentally benign process for the conversion of carbohydrates into furfural.
• Wu, Changyan,Chen, Wei,Zhong, Linxin,Peng, Xinwen,Sun, Runcang,Fang, Junjie,Zheng, Shaobo

• p. 7430 - 7435

  (2014)
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• Enhanced Furfural Yields from Xylose Dehydration in the Γ-Valerolactone/Water Solvent System at Elevated Temperatures
• High yields of furfural (>90 %) were achieved from xylose dehydration in a sustainable solvent system composed of γ-valerolactone (GVL), a biomass derived solvent, and water. It is identified that high reaction temperatures (e.g., 498 K) are required to achieve high furfural yield. Additionally, it is shown that the furfural yield at these temperatures is independent of the initial xylose concentration, and high furfural yield is obtained for industrially relevant xylose concentrations (10 wt %). A reaction kinetics model is developed to describe the experimental data obtained with solvent system composed of 80 wt % GVL and 20 wt % water across the range of reaction conditions studied (473–523 K, 1–10 mm acid catalyst, 66–660 mm xylose concentration). The kinetic model demonstrates that furfural loss owing to bimolecular condensation of xylose and furfural is minimized at elevated temperature, whereas carbon loss owing to xylose degradation increases with increasing temperature. Accordingly, the optimal temperature range for xylose dehydration to furfural in the GVL/H2O solvent system is identified to be from 480 to 500 K. Under these reaction conditions, furfural yield of 93 % is achieved at 97 % xylan conversion from lignocellulosic biomass (maple wood).
• Sener, Canan,Motagamwala, Ali Hussain,Alonso, David Martin,Dumesic, James A.

• p. 2321 - 2331

  (2018)
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• Production of furfural from xylose and corn stover catalyzed by a novel porous carbon solid acid in γ-valerolactone
• A resorcinol-formaldehyde resin carbon (RFC) catalyst with a well-developed, ordered, mesoporous framework was prepared using a soft template method at room temperature. The carbon was sulfonated in water using sulfanilic acid under mild atmospheric conditions. The sulfonated RFC (S-RFC) was characterized by N2 adsorption-desorption, elemental analysis, TEM, XPS, and FT-IR. It was determined that S-RFC is an efficient solid acid catalyst for furfural production from xylose and corn stover in γ-valerolactone (GVL). The effects of reaction time, reaction temperature, catalyst loading, substrate dosage and water concentration were investigated. 80% furfural yield and 100% xylose conversion were obtained from xylose at 170 °C in 15 min with 0.5 g catalyst. Comparatively, 68.6% furfural yield was achieved from corn stover at 200 °C in 100 min when using 0.6 g catalyst. Since there was no discernable decrease in furfural yield after multiple conversions utilizing the same catalyst, the recyclability of the catalyst is considered good.
• Zhu, Yuanshuai,Li, Wenzhi,Lu, Yijuan,Zhang, Tingwei,Jameel, Hasan,Chang, Hou-Min,Ma, Longlong

• p. 29916 - 29924

  (2017)
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• Reactive Extraction Enhanced by Synergic Microwave Heating: Furfural Yield Boost in Biphasic Systems
• Reactive extraction is an emerging operation in the industry, particularly in biorefining. Here, reactive extraction was demonstrated, enhanced by microwave irradiation to selectively heat the reactive phase (for efficient reaction) without unduly heating the extractive phase (for efficient extraction). These conditions aimed at maximizing the asymmetries in dielectric constants and volumes of the reaction and extraction phases, which resulted in an asymmetric thermal response of the two phases. The efficiency improvement was demonstrated by dehydrating xylose (5 wt percent in water) to furfural with an optimal yield of approximately 80 mol percent compared with 60–65 mol percent under conventional biphasic conditions, which corresponds to approximately 50 percent reduction of byproducts.
• Huskens, Jurriaan,Lange, Jean-Paul,Ricciardi, Luca,Verboom, Willem

• (2020)
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• One-step Preparation of Carbon-based Solid Acid Catalyst from Water Hyacinth Leaves for Esterification of Oleic Acid and Dehydration of Xylose
• Carbon-based solid acid catalysts were successfully obtained via one-step hydrothermal carbonization (HTC) of water hyacinth (WH) in the presence of p-toluenesulfonic acid (PTSA). Increasing the HTC temperature from 180 to 240 °C resulted in carbonaceous materials with increased sulfur content and less adsorbed water. The material obtained at 220 °C (WH-PTSA-220) contains the highest amount of acid sites and promotes the highest initial rate of two transformations, that is, methanolysis of oleic acid and dehydration of xylose to furfural. While all PSTA-treated WH catalysts gave comparable fatty acid conversions (≈97 %) and furfural yields (≈60 %) after prolonged reaction times, the WH-PTSA-240 system bearing a relatively low acid density maintains the most favorable reusability profile. Higher HTC temperatures (220–240 °C) improved the catalyst reusability profiles due to graphitization and hydrophobicity of the carbon surface. The catalyst systems derived herein from biomass may have potential applications in biorefining platforms, utilizing the conversion of waste biomass to chemicals.
• Laohapornchaiphan, Jutitorn,Smith, Christopher B.,Smith, Siwaporn Meejoo

• p. 3178 - 3186

  (2017)
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• Low-Temperature Continuous-Flow Dehydration of Xylose Over Water-Tolerant Niobia–Titania Heterogeneous Catalysts
• The sustainable conversion of vegetable biomass-derived feeds to useful chemicals requires innovative routes meeting environmental and economical criteria. The approach herein pursued is the synthesis of water-tolerant, unconventional solid acid monolithic catalysts based on a mixed niobia–titania skeleton building up a hierarchical open-cell network of meso- and macropores, and tailored for use under continuous-flow conditions. The materials were characterized by spectroscopic, microscopy, and diffraction techniques, showing a reproducible isotropic structure and an increasing Lewis/Br?nsted acid sites ratio with increasing Nb content. The catalytic dehydration reaction of xylose to furfural was investigated as a representative application. The efficiency of the catalyst was found to be dramatically affected by the niobia content in the titania lattice. The presence of as low as 2 wt % niobium resulted in the highest furfural yield at 140 °C under continuous-flow conditions, by using H2O/γ-valerolactone as a safe monophasic solvent system. The interception of a transient 2,5-anhydroxylose species suggested the dehydration process occurs via a cyclic intermediates mechanism. The catalytic activity and the formation of the anhydro intermediate were related to the Lewis acid sites (LAS)/Br?nsted acid sites (BAS) ratio and indicated a significant contribution of xylose–xylulose isomerization. No significant catalyst deactivation was observed over 4 days usage.
• Moreno-Marrodan, Carmen,Barbaro, Pierluigi,Caporali, Stefano,Bossola, Filippo

• p. 3649 - 3660

  (2018)
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• Catalytic dehydration of xylose to furfural: Vanadyl pyrophosphate as source of active soluble species
• The acid-catalysed, aqueous phase dehydration of xylose (a monosaccharide obtainable from hemicelluloses, e.g., xylan) to furfural was investigated using vanadium phosphates (VPO) as catalysts: the precursors, VOPO4· 2H2O, VOHPO4·0.5H2O and VO(H 2PO4)2, and the materials prepared by calcination of these precursors, that is, γ-VOPO4, (VO) 2P2O7 and VO(PO3)2, respectively. The VPO precursors were completely soluble in the reaction medium. In contrast, the orthorhombic vanadyl pyrophosphate (VO)2P 2O7, prepared by calcination of VOHPO4· 0.5H2O at 550 °C/2 h, could be recycled by simply separating the solid acid from the reaction mixture by centrifugation, and no drop in catalytic activity and furfural yields was observed in consecutive 4 h-batch runs (ca. 53% furfural yield, at 170 °C). However, detailed catalytic/characterisation studies revealed that the vanadyl pyrophosphate acts as a source of active water-soluble species in this reaction. For a concentration of (VO) 2P2O7 as low as 5 mM, the catalytic reaction of xylose (ca. 0.67 M xylose in water, and toluene as solvent for the in situ extraction of furfural) gave ca. 56% furfural yield, at 170 °C/6 h reaction.
• Sádaba, Irantzu,Lima, Sérgio,Valente, Anabela A.,López Granados, Manuel

• p. 2785 - 2791

  (2011)
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• Furfural formation from D-xylose: The use of different halides in dilute aqueous acidic solutions allows for exceptionally high yields
• Starting from the results achieved in a previous work on the effects of Cl- ions on furfural formation in aqueous acid solution [Marcotullio, G. et al., Green Chem. 2010, 12, 1739], the general effect of different halides is addressed. Experimental results show the halides to influence at least two distinct steps in the reaction leading from d-xylose to furfural under acidic conditions, via different mechanisms. The nucleophilicity of the halides appears to be critical for the dehydration, but not for the initial enolization reaction. By combining different halides synergic effects become evident resulting in very high selectivities and furfural yields.
• Marcotullio,De Jong

• p. 1291 - 1293

  (2011)
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• Production of furfural from xylose at atmospheric pressure by dilute sulfuric acid and inorganic salts
• In this paper, the dehydration of xylose to furfural was carried out under atmospheric pressure and at the boiling temperature of a biphasic mixture of toluene and an aqueous solution of xylose, with sulfuric acid as catalyst plus an inorganic salt (NaCl or FeCl3) as promoter. The best yield of furfural was 83% under the following conditions: 150 mL of toluene and 10 mL of aqueous solution of 10% xylose (w/w), 10% H2SO4 (w/w), 2.4 g NaCl, and heating for 5 h. FeCl3 as promoter was found to be more efficient than NaCl. The addition of DMSO to the aqueous phase in the absence of an inorganic salt was shown to improve the yield of furfural.
• Rong, Chunguang,Ding, Xuefeng,Zhu, Yanchao,Li, Ying,Wang, Lili,Qu, Yuning,Ma, Xiaoyu,Wang, Zichen

• p. 77 - 80

  (2012)
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• Catalytic cyclodehydration of xylose to furfural in the presence of zeolite H-Beta and a micro/mesoporous Beta/TUD-1 composite material
• The batch-wise and aqueous phase cyclodehydration of d-xylose to furfural (FUR) at 170 °C has been investigated in the presence of a composite material consisting of zeolite Beta nanocrystals (Si/Al = 12) embedded in a purely siliceous TUD-1 mesoporous matrix (BEATUD), characterised by elemental analysis, powder XRD, TEM and N2 sorption. After 8 h the xylose conversion reached 98% and the FUR yield was 74%. The initial reaction rates for BEATUD and the bulk nanocrystalline zeolite Beta (BEA) were similar when expressed on the basis of the total amount of acid sites (Lewis + Br?nsted) determined through FTIR analysis of adsorbed pyridine. However, the FUR yields at high xylose conversions of ca. 98% were higher for BEATUD (74%) than for bulk BEA (54%). TGA and DSC analyses for recovered catalysts showed that BEATUD possessed a lower amount of carbonaceous matter after a catalytic run, suggesting that the improved performance of the composite may be due to favourable competitive adsorption effects caused by the surrounding silica matrix. By thermally removing the carbonaceous matter between consecutive batch runs, BEATUD could be repeatedly reused without loss of catalytic performance.
• Lima, Sérgio,Antunes, Margarida M.,Fernandes, Auguste,Pillinger, Martyn,Ribeiro, Maria Filipa,Valente, Anabela A.

• p. 141 - 148

  (2010)
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• Catalytic conversion of xylose to furfural by p-toluenesulfonic acid (Ptsa) and chlorides: Process optimization and kinetic modeling
• Furfural is one of the most promising precursor chemicals with an extended range of downstream derivatives. In this work, conversion of xylose to produce furfural was performed by employing p-toluenesulfonic acid (pTSA) as a catalyst in DMSO medium at moderate temperature and atmospheric pressure. The production process was optimized based on kinetic modeling of xylose conversion to furfural alongwith simultaneous formation of humin from xylose and furfural. The synergetic effects of organic acids and Lewis acids were investigated. Results showed that the catalyst pTSA-CrCl3·6H2 O was a promising combined catalyst due to the high furfural yield (53.10%) at a moderate temperature of 120? C. Observed kinetic modeling illustrated that the condensation of furfural in the DMSO solvent medium actually could be neglected. The established model was found to be satisfactory and could be well applied for process simulation and optimization with adequate accuracy. The estimated values of activation energies for xylose dehydration, condensation of xylose, and furfural to humin were 81.80, 66.50, and 93.02 kJ/mol, respectively.
• Sajid, Muhammad,Rizwan Dilshad, Muhammad,Saif Ur Rehman, Muhammad,Liu, Dehua,Zhao, Xuebing

• (2021)
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• Efficient catalytic conversion of corn stalk and xylose into furfural over sulfonated graphene in γ-valerolactone
• Sulfonated graphene (SG) was prepared and employed to convert corn stalk and xylose into furfural. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR) were used to characterize SG. The effects of reaction time, temperature, substrate loading, catalyst dosage and solvents on the reaction were researched and optimized. SG exhibited high catalytic activity in the conversion of xylose and corn stalk to furfural. A fairly high furfural yield of 96% was achieved at 150 °C from xylose and a 71.9% furfural yield was obtained when using a 10.7 ratio (mass ratio: xylose to SG) at 140 °C. While a 48% furfural yield was obtained from corn stalk (based on the starting combined moles of xylan and glucan in corn stalk; yield was >100%, if based on only xylan) using a substrate loading (corn stalk to catalyst mass ratio) of 2.14 and a 19% 5-hydroxymethylfurfural (5-HMF) yield was obtained. What's more, a 43.9% yield of furfural was obtained in only 20 min. In addition, the reusability of SG was also investigated and shown to have good stability for xylose dehydration.
• Ma, Jianru,Li, Wenzhi,Guan, Shengnan,Liu, Qiying,Li, Qingqing,Zhu, Chaofeng,Yang, Tao,Ogunbiyi, Ajibola Temitope,Ma, Longlong

• p. 10569 - 10577

  (2019)
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• P -Hydroxybenzenesulfonic acid-formaldehyde solid acid resin for the conversion of fructose and glucose to 5-hydroxymethylfurfural
• A novel solid p-hydroxybenzenesulfonic acid-formaldehyde resin (SPFR) was prepared via a straightforward hydrothermal method. The catalytic properties of SPFR solid acids were evaluated in the dehydration reaction of fructose and glucose to 5-hydroxymethylfurfural (HMF). SEM, TEM, N2 adsorption-desorption, elemental analysis (EA), thermogravimetric analysis (TGA), and FT-IR were used to explore the effects of catalyst structure and composition on the HMF preparation from fructose. The effects of reaction time and temperature on the dehydration of fructose and glucose were also investigated. An HMF yield as high as 82.6% was achieved from fructose at 140 °C after 30 min, and 33.0% was achieved from glucose at 190 °C in 30 min. Furthermore, the recyclability of SPFR for the HMF production from fructose in 5 cycles was good.
• Li, Wenzhi,Zhang, Tingwei,Xin, Haosheng,Su, Mingxue,Ma, Longlong,Jameel, Hason,Chang, Hou-Min,Pei, Gang

• p. 27682 - 27688

  (2017)
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• The optimization of formic acid hydrolysis of xylose in furfural production
• Formic acid, a byproduct of furfural process, can be an effective catalyst for dehydration of xylose into furfural. Due to the low corrosion resistance, easy to be separated and reused, there is a growing interest in the use of formic acid as catalyst. In this study, response surface methodology (RSM) was used to optimize the hydrolysis process in order to obtain high furfural yield and selectivity. Three important parameters, initial xylose concentration (40-120 g/L), temperature (170-190 °C), formic acid concentration (5-15 g/L) were optimized. The optimum initial xylose concentration, formic concentration, reaction temperature were 40 g/L, 10 g/L, and 180 °C, respectively. Under these conditions, the maximum furfural yield of 74% and selectivity of 78% were achieved.
• Yang, Wandian,Li, Pingli,Bo, Dechen,Chang, Heying

• p. 53 - 61

  (2012)
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• Mesoporous Nb2O5 as solid acid catalyst for dehydration of d-xylose into furfural
• The acid-catalyzed dehydration of d-xylose to furfural has been investigated in a biphasic water-toluene system, using a mesoporous Nb 2O5 catalyst prepared by a neutral templating route. The catalytic behavior was compared with a commercial Nb2O5. Materials were characterized by XRD, XPS, TEM, NH3-TPD, Raman spectroscopy and N2 sorption. The d-xylose conversion and furfural yield over the mesoporous niobia were found to increase with reaction temperature and time, in such a way that at 170 °C and 90 min, a d-xylose conversion and a furfural yield were higher than 90% and 50%, respectively. However, the commercial crystalline niobia displayed a low activity. The stability of the mesoporous catalyst has been demonstrated by XRD and N 2 sorption, and corroborated by the absence of significant niobium leaching in solution.
• García-Sancho,Rubio-Caballero,Mérida-Robles,Moreno-Tost,Santamaría-González,Maireles-Torres

• p. 119 - 124

  (2014)
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• Cleavage of DNA by proton-coupled electron transfer to a photoexcited, hydrated Ru(II) 1,10-phenanthroline-5,6-dione complex
• Visible light irradiation of a ruthenium(II) quinone-containing complex, [(phen)2Ru(phendione)]2+ (12+), where phendione = 1,10-phenanthroline-5,6-dione, leads to DNA cleavage in an oxygen independent manner. A combination of NMR analyses, transient absorption spectroscopy, and fluorescence measurements in water and acetonitrile reveal that complex 1 2+ must be hydrated at the quinone functionality, giving [(phen) 2Ru(phenH2O)]2+ (1H2O2+, where phenH2O = 1,10-phenanthroline-6-one-5-diol), in order to access a long-lived 3MLCThydrate state (τ ～ 360 ns in H2O) which is responsible for DNA cleavage. In effect, hydration at one of the carbonyl functions effectively eliminates the low-energy 3MLCTSQ state (RuIII phen-semiquinone radical anion) as the predominant nonradiative decay pathway. This 3MLCT SQ state is very short-lived (2O2+* has photophysical properties similar to the 3MLCT state in [Ru(phen) 3]2+* with the added functionality of basic sites at the ligand periphery. Whereas [Ru(phen)3]2+* does not show direct DNA cleavage, the deprotonated form of 1H2O 2+* does via a proton-coupled electron transfer (PCET) mechanism where the peripheral basic oxygen sites act as the proton acceptor. Analysis of the small molecule byproducts of DNA scission supports the conclusion that cleavage occurs via H-atom abstraction from the sugar moieties, consistent with a PCET mechanism. Complex 12+ is a rare example of a ruthenium complex which 'turns on' both reactivity and luminescence upon switching to a hydrated state.
• Poteet, Steven A.,Majewski, Marek B.,Breitbach, Zachary S.,Griffith, Cynthia A.,Singh, Shreeyukta,Armstrong, Daniel W.,Wolf, Michael O.,MacDonnell, Frederick M.

• p. 2419 - 2422

  (2013)
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• Dehydration of biomass to furfural catalyzed by reusable polymer bound sulfonic acid (PEG-OSO3H) in ionic liquid
• Polymer bound sulfonic acid (PEG-OSO3H) is active for the dehydration of biomass to furfural. The furfural yield is improved when MnCl2 is added to the reaction mixture. The catalyst was mild, non-volatile, and non-corrosive and can be recycled multiple times (>10) without an intermediate regeneration step and no significant leaching of -OSO3H groups is observed.
• Zhang, Zhang,Du, Bin,Quan, Zheng-Jun,Da, Yu-Xia,Wang, Xi-Cun

• p. 633 - 638

  (2014)
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• The formation of 2-furaldehyde and formic acid from pentoses in slightly acidic deuterium oxide studied by 1H NMR spectroscopy
• The title reaction at 96 deg C and pD 1.5, 3.0, or 4.5 was followed by 1H NMR spectroscopy.The rate on pentose degradation increased in the order: arabinose ca. xyloseribose2-pentuloses.At pD 1.5, the rate of 2-furaldehyde formation increased in the same order.Increasing pD strongly accelerated the degradation of the aldoses but slightly retarded that of the ketoses.Increasing pD also retarded the formation of 2-furaldehyde, particularly from the ketoses, and increased its deuterium content at H-α (from 8-25 to 50-83 atom percent) and H-3 (from 79-100 to 100 atom percent).This is explained by assuming that 2-furaldehyde had formed mainly via acyclic intermediates, with reversible formation of a 3-deoxypentosulose.The formation of formic acid was slow and did not proceed via 2-furaldehyde.As evident from experiments with 1- or 5-13C-substituted aldopentoses, the formic acid was derived exclusively from the terminal pentose carbons, C-1 being somewhat more important than C-5.Keywords: Formic acid; 2-Furaldehyde; Pentose
• Ahmad, Tania,Kenne, Lennart,Olsson, Kjell,Theander, Olof

• p. 309 - 320

  (1995)
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• Highly efficient and selective CO2-adjunctive dehydration of xylose to furfural in aqueous media with THF
• The selective dehydration of xylose into furfural using high-pressure CO2 as an effective and more sustainable catalyst in an H2O/THF system is reported for the first time. The conversion of d-xylose into furfural above 83 mol% with a furfural yield of 70 mol% and a selectivity of 84% was achieved with only 50 bar of CO2 pressure within 1 hour at 180 °C.
• Morais, Ana Rita C.,Bogel-Lukasik, Rafal

• p. 2331 - 2334

  (2016)
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• Furfural production from rice husk using sulfuric acid and a solid acid catalyst through a two-stage process
• This study aimed to optimize the conditions for furfural production from rice husk via a two-stage process: acid hydrolysis followed by dehydration using an orthogonal test design and response surface methodology, respectively. Orthogonal test design was utilized in the hydrolysis step; optimum conditions were as follows: 2.5% sulfuric acid (mass fraction), 110 °C reaction temperature, sulfuric acid to rice husk (L/S) ratio of 8 (g/mL), and a reaction time of 3 h. According to the Box-Behnken design, the temperature, amount of catalyst, extractant volume, and reaction time were chosen as four important factors with three levels for the dehydration step. Conditions were further optimized by response surface analysis. The results showed that the optimal conditions were 177 °C, 120 mL extractant volume, 2.1 g of catalyst, and a reaction time of 4.8 h. Under the optimal conditions, the furfural yield reached 8.9%, which is consistent with the estimated value, 8.97%.
• Suxia, Ren,Haiyan, Xu,Jinling, Zhu,Shunqing, Li,Xiaofeng, He,Tingzhou, Lei

• p. 1 - 6

  (2012)
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• A modified biphasic system for the dehydration of d-xylose into furfural using SO42-/TiO2-ZrO2/La 3+ as a solid catalyst
• One of the most promising strategies for furfural production is to extract continually the target product from the aqueous solution utilizing organic solvents. With the aim to develop an ecologically viable catalytic pathway for furfural production without the addition of mineral acids, we presented a modified biphasic system using a solid acid (SO42-/ TiO2-ZrO2/La3+) as catalyst for producing furfural from xylose. Different kinds of aprotic organic solvents (DMSO, DMF and DMI) in water phase and 2-butanol in organic phase (MIBK) were investigated as reaction media. Furfural yield and xylose conversion efficiency were dependent on the amounts of aprotic organic solvents and 2-butanol, the solid/liquid ratio, and the volume ratio of the organic phase and the aqueous phase as well as the reaction temperature and time. As a result, DMI showed the best performance on improving furfural yield during the furfural production. 3563.3 μmol of furfural/g of xylose with 97.9% xylose conversion efficiency was obtained after 12 h at 180 °C when the volume ratios of water to DMI and MIBK to 2-butanol were 8:2 and 7:3, respectively.
• Li, Huiling,Deng, Aojie,Ren, Junli,Liu, Changyu,Wang, Wenju,Peng, Feng,Sun, Runcang

• p. 251 - 256

  (2014)
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• Synthesis of furfural from d-xylose and corncob with chromium chloride as catalyst in biphasic system
• An efficient process was developed for the conversion of D-xylose into furfural with chromium chloride as catalyst in a biphasic system. The optimal furfural yield of 38.76 % was obtained in the following reaction conditions: reaction temperature 140 °C, reaction time 1 h and the catalyst loading 2 mmol. Sodium chloride used as co-catalyst was found to affect the furfural yield. A higher furfural yield of 52.55 % was achieved in the presence of 3 g of sodium chloride when using chromium chloride catalyst for the dehydration of D-xylose into furfural. The CrCl3·6H2O-NaCl catalytic system could be recycled and its stable activity was showed after three successive runs. Moreover, this work also provided useful information for the production of furfural from biomass. The furfural yield of 23.88 % was achieved when corncob used as starting materials.
• Zhang, Ye,Chen, Mingqiang,Wang, Jun,Hu, Qingsong

• p. 1717 - 1720

  (2014)
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• Catalytic dehydration of D-xylose to furfural over a tantalum-based catalyst in batch and continuous process
• Furfural is a biomass-based bulk chemical and its derivatives have potential applications as renewable fuels and chemicals. A water-tolerant and stable solid acid catalyst modified hydrated tantalum oxide (TA-p) was developed for catalytic conversion of D-xylose to furfural in water-organic solvent biphasic system. This process was performed both in a batch reactor and a continuous fixed-bed reactor. In the batch process, D-xylose conversion and furfural yield were significantly affected by the organic solvent, reaction temperature and reaction time. 1-Butanol, which could be obtained through the fermentation of biomass-based carbohydrates, was selected as organic phase and the highest furfural yield of 59% was achieved with D-xylose conversion of 96% at 180 °C in the continuous process. Moreover, the long-time stability test for 80 h under the optimal conditions showed the excellent stability of TA-p catalyst.
• Li, Xing-Long,Pan, Tao,Deng, Jin,Fu, Yao,Xu, Hua-Jian

• p. 70139 - 70146

  (2015)
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• Conversion of C5 carbohydrates into furfural catalyzed by a Lewis acidic ionic liquid in renewable γ-valerolactone
• For the purpose of building a green reaction system to produce furfural (FF), the conversion of two important pentoses from hemicellulose, namely xylose and arabinose, was investigated in an aqueous reaction system including a Lewis acidic ionic liquid as a catalyst and renewable γ-valerolactone (GVL) as a co-solvent. The results showed that the introduction of GVL greatly improved the reactivity of pentose and inhibited the secondary decomposition reaction of FF compared to a pure-water reaction system. NMR analysis suggested that the composition of pentose conformers was greatly altered towards a reactive distribution. The highest FF yields were 79.76% (from xylose) and 58.70% (from arabinose), which were obtained at 140 °C. The influence of reaction parameters on pentose conversion was also studied. A comparison between different reaction conditions suggested that arabinose had less reactivity than xylose, leading to its lower conversion rate and FF yield. Furthermore, xylan and real biomass materials were tested in the proposed reaction system, and decent FF yields of up to 69.66% (from xylan) and 47.96% (from corn stalk) were obtained.
• Wang, Shurong,Zhao, Yuan,Lin, Haizhou,Chen, Jingping,Zhu, Lingjun,Luo, Zhongyang

• p. 3869 - 3879

  (2017)
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• Synthesis of furfural from xylose by heterogeneous and reusable nafion catalysts
• Nafion 117 has been proven as a robust and reusable heterogeneous catalyst for the dehydration of 9.1% (w/w) xylose in dimethyl sulfoxide (DMSO) to yield 60% furfural in 2 h at 150°C. The catalytic high activity promoted shorter reaction times to limit the formation of side-products which otherwise would lead to decreased yields. Within the allowable operating temperature range of Nafion (125 to 175°C), the reaction was kinetically controlled. In corroboration with AFM and SEM imaging, ATR-FTIR confirmed that the Nafion catalytic activity remained unchanged after 15 repeated uses. With excellent chemical and thermal stability under the conditions for xylose dehydration compared to existing solid acid catalysts, this reusable Nafion system could be a step towards the more economical production of furfural from renewable biomass, an intermediate chemical for the preparation of value-added chemicals.
• Lam, Edmond,Majid, Ehsan,Leung, Alfred C. W.,Chong, Jonathan H.,Mahmoud, Khaled A.,Luong, John H. T.

• p. 535 - 541

  (2011)
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• Furfural synthesis from D-xylose in the presence of sodium chloride: Microwave versus conventional heating
• We investigate the existence of specific/nonthermal microwave effects for the dehydration reaction of xylose to furfural in the presence of NaCl. Such effects are reported for sugars dehydration reactions in several literature reports. To this end, we adopted three approaches that compare microwave-assisted experiments with a) conventional heating experiments from the literature; b) simulated conventional heating experiments using microwave-irradiated silicon carbide (SiC) vials; and at c) different power levels but the same temperature by using forced cooling. No significant differences in the reaction kinetics are observed using any of these methods. However, microwave heating still proves advantageous as it requires 30% less forward power compared to conventional heating (SiC vial) to achieve the same furfural yield at a laboratory scale.
• Xiouras, Christos,Radacsi, Norbert,Sturm, Guido,Stefanidis, Georgios D.

• p. 2159 - 2166

  (2016)
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• Synthesis, kinetic study, and applications of polyethyleneimine supported nano zirconium chromate in oxidation of furfuryl alcohol to corresponding carbonyl compound
• The efficiency of highly branched polyethyleneimine has been investigated as a support for nano zirconium chromate and subsequent use as a heterogeneous oxidant for selective oxidation of furfuryl alcohol to furfural. These were synthesized using polyethyleneimine to produce a polymer coordinated nano zirconium, a noble and straightforward method for screening high catalytically active polymer nano composites. The one-step systematic derivatization of the polyethyleneimine scaffold led structurally correlated to the stabilization of zirconium nanoparticles and catalysis. Analysis of this polymeric reagent identified the zirconium chromate nano composite that was able to be effective to oxidation reaction in tetrahydrofuran under mild conditions due to the surface area of the nano zirconium chromate per unit volume. Capacity of the reagent and fixation of nano zirconium chromate is confirmed by ICP and atomic absorption technique. Morphology of this nano composite is investigated by SEM and TEM. The kinetic of oxidation of furfuryl alcohol, over heterogeneous catalyst, nano zirconium chromate in THF, were investigated. Power-law rate model was applied to describe the experimental results and obtain the orders of the reaction with respect to furfuryl alcohol, catalyst, and furfural, which were found to be 0.989, 0.991, and ?0.68, respectively, with the activation energy of 76.78?kJ/mol. Graphical abstract: [Figure not available: see fulltext.]
• Sheikh, Setareh,Goudarzian, Nooredin

• p. 1531 - 1538

  (2016)
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• Microwave assisted efficient furfural production using nano-sized surface-sulfonated diamond powder
• Sulfonated nano-sized diamond powder (S-DP) was tested in a typical water-CPME (1:3, v/v) biphasic system and heated in a commercial monowave microwave oven to promote the dehydration of D-xylose into furfural as industrial platform molecule. This new heterogeneous catalyst with a propyl linker between the support and the sulfonyl group expressed remarkable sufficient hydrophilicity, affinity for D-xylose and catalytic activity in presence of NaCl. The solid can act as a strong acidic catalyst without detectable exchange between proton exclusively localized on the surface of the catalyst and sodium ion. It was also stable at 200 °C even after severe recycling treatment. The final optimized condition requires 10 wt% of the catalyst for a maximum furfural yield of 76% when the mixture is heated for 50 min in the current biphasic system.
• Delbecq, Frederic,Takahashi, Yukari,Kondo, Takeshi,Corbas, Cristobal Cara,Ramos, Encarnacion Ruiz,Len, Christophe

• p. 74 - 78

  (2018)
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• The role of metal halides in enhancing the dehydration of xylose to furfural
• The dehydration of xylose yields furfural, a product of considerable value as both a commodity chemical and a platform for producing a variety of fuels. When xylose is dehydrated in aqueous solution in the presence of a Bronsted acid catalyst, humins are formed via complex side processes that ultimately result in a loss in the yield of furfural. Such degradative processes can be minimized via the insitu extraction of furfural into an organic solvent. The partitioning of furfural from water into a given extracting solvent can be enhanced by the addition of salt to the aqueous phase, a process that increases the thermodynamic activity of furfural in water. Although the thermodynamics of using salts to improve liquid-liquid extraction are well studied, their impact on the kinetics of xylose dehydration catalyzed by a Bronsted acid are not. The aim of the present study was to understand how metal halide salts affect the mechanism and kinetics of xylose dehydration in aqueous solution. We found that the rate of xylose consumption is affected by both the nature of the salt cation and anion, increasing in the order no salt+++ and no salt---. Furfural selectivity increases similarly with respect to metal cations, but in the order no salt--- for halide anions. Multinuclear NMR was used to identify the interactions of cations and anions with xylose and to develop a model for explaining xylose-metal halide and water-metal halide interactions. The results of these experiments coupled with 18O-labeling experiments indicate that xylose dehydration is initiated by protonation at the C1OH and C2OH sites, with halide anions acting to stabilize critical intermediates. The means by which metal halides affect the formation of humins was also investigated, and the role of cations and anions in affecting the selectivity to humins is discussed. Get your kicks from kinetics: The effect of metal halides on the mechanism and kinetics of xylose dehydration in aqueous solution have been investigated. We found that both the rate of xylose consumption and furfural selectivity are affected by the nature of the salt cation and anion pairing.
• Enslow, Kristopher R.,Bell, Alexis T.

• p. 479 - 489

  (2015)
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• Synergistic effect between CaCl2 and Γ-Al2O3 for furfural production by dehydration of hemicellulosic carbohydrates
• γ-Al2O3 has successfully been used as solid acid catalyst for xylose dehydration in a water:toluene biphasic system. The addition of alkaline earth metal chlorides improved the partition coefficient, thus facilitating the extraction of furfural from the aqueous phase. In this sense, the best catalytic performance was attained by using CaCl2 and γ-Al2O3 with almost full xylose conversion and a furfural yield of 55% after 50 min, at 150 °C. A 1H NMR study has demonstrated that CaCl2 shifts the α-xylopyranose/β-xylopyranose anomeric equilibrium toward the α-form, more favorable for initiating the dehydration process, and γ-Al2O3 promotes the furfural production. γ-Al2O3 can be reused during ten catalytic cycles without any pretreatment. Finally, the synergistic effect between CaCl2 and γ-Al2O3 could also be inferred from the increase in furfural yield, until a value of 83% after 50 min at 175 °C, by using a hemicellulosic liquor obtained from olive stones.
• Fúnez-Nú?ez,García-Sancho,Cecilia,Moreno-Tost,Pérez-Inestrosa,Serrano-Cantador,Maireles-Torres

• (2019)
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• Furfural from corn stover hemicelluloses. A mineral acid-free approach
• Furfural was obtained from corn stover hemicelluloses by a microwave-assisted, green and heterogeneously catalyzed two-step cascade process as follows: first step, hydrothermal fractionation of corn stover hemicelluloses, and second step, hydrolysis/dehydration of soluble hemicellulosic sugars over niobium phosphate to yield furfural at moderate temperatures (200 °C), with both steps being performed in water. Furfural yields of up to 23 mol% with respect to the starting raw biomass were reached. This journal is the Partner Organisations 2014.
• Gomez Bernal, Hilda,Bernazzani, Luca,Raspolli Galletti, Anna Maria

• p. 3734 - 3740

  (2014)
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• Hydrochloric acid-catalyzed coproduction of furfural and 5-(chloromethyl)furfural assisted by a phase transfer catalyst
• Furfural has been produced in 53percent isolated yield from D-xylose within an aqueous HCl-1,2-dichloroethane biphasic reaction mixture using benzyltributylammonium chloride (BTBAC) as a phase transfer catalyst. The use of BTBAC noticeably improved the yield of furfural compared to that in the control reaction. The reaction was optimized on the reaction temperature, duration, concentration of HCl, and the loading of BTBAC. Furfural and 5-(chloromethyl)furfural (CMF) have also been coproduced from a mixture of pentose and hexose sugars. Under optimized conditions (100 °C, 3 h, 20.2percent HCl, 10 wtpercent BTBAC), CMF and furfural were isolated in 17percent and 53percent yield, respectively, from a mixture of glucose and xylose. In addition, levulinic acid was isolated from the aqueous layer in 31percent yield.
• Bhat, Navya Subray,Dutta, Saikat,Onkarappa, Sharath Bandibairanahalli,Vinod, Nivedha

• (2020)
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• One-pot sustainable synthesis of valuable nitrogen compounds from biomass resources
• In this work we report a new one-pot process for the sustainable synthesis of 2-furanylquinazolines and 2-furfurylidene derivatives from carbohydrates, including xylose, fructose and xylan, with moderate overall yields, catalyzed by perrhenic acid.
• Carreira, M. Carolina A.,Fernandes, Ana C.,Oliveira, M. Concei??o

• (2022/01/11)
• 

• Characteristic flavor formation of thermally processed N-(1-deoxy-α-D-ribulos-1-yl)-glycine: Decisive role of additional amino acids and promotional effect of glyoxal
• The role of amino acids and α-dicarbonyls in the flavor formation of Amadori rearrangement product (ARP) during thermal processing was investigated. Comparisons of the volatile compounds and their concentrations when N-(1-deoxy-α-D-ribulos-1-yl)-glycine r
• Zhan, Huan,Cui, Heping,Yu, Junhe,Hayat, Khizar,Wu, Xian,Zhang, Xiaoming,Ho, Chi-Tang

• (2021/09/28)
• 

• Ethanolysis of selected catalysis by functionalized acidic ionic liquids: An unexpected effect of ILs structural functionalization on selectivity phenomena
• A series of functionalized hydrogen sulfate imidazolium ILs were synthesized and applied as catalysts in the reaction of glucose, xylose and fructose with ethanol. In this research, an unexpected selectivity phenomenon was observed. It showed that in this reaction functionalized ILs should be considered as a special type of catalyst. Functionalization of alkyl imidazolium ILs, especially the addition of electronegative OH groups, causes a clear and unexpected effect manifested via visible changes in the selectivity of the reaction studied. In the case of fructose, an increase in the number of OH groups affects an increase in the selectivity towards ethyl levulinate from 14.2% for [bmim]HSO4 to 20.1% for [glymim]HSO4 with an additional increase in selectivity to 5-hydroxymethyfurfural. In turn, for xylose, the introduction of OH groups to the alkyl chain was manifested by a decrease in selectivity to furfural as its ethyl acetal and an increase in selectivity to ethylxylosides. This journal is
• Nowakowska-Bogdan, Ewa,Nowicki, Janusz

• p. 1857 - 1866

  (2022/02/05)
• 

• Controlled reduction of activated primary and secondary amides into aldehydes with diisobutylaluminum hydride
• A practical method is disclosed for the reduction of activated primary and secondary amides into aldehydes using diisobutylaluminum hydride (DIBAL-H) in toluene. A wide range of aryl and alkyl N-Boc, N,N-diBoc and N-tosyl amides were converted into the corresponding aldehydes in good to excellent yields. Reduction susceptible functional groups such as nitro, cyano, alkene and alkyne groups were found to be stable. Broad substrate scope, functional group compatibility and quick conversions are the salient features of this methodology.
• Azeez, Sadaf,Kandasamy, Jeyakumar,Sabiah, Shahulhameed,Sureshbabu, Popuri
• supporting information

  p. 2048 - 2053

  (2022/03/31)
• 

• Nickel catalyzed hydrosilane reduction of (het)arenecarboxylic acids into aldehydes
• Nickel-catalyzed reduction of (het)arenecarboxylic acids with hydrosilanes in the presence of dimethyl dicarbonate as the activator affords the corresponding aldehydes. The role of the activator is the conversion of the acids into their anhydrides undergoing C–O cleavage. The good yields were achieved in case of substrates bearing electron-donating and electron-neutral groups.
• Wang, Liang,Wang, Yaoyao,Tao, Yu,Zhang, Nana,Li, Shubai

• p. 271 - 273

  (2021/05/04)
• 

• Au-catalyzed electrochemical oxidation of alcohols using an electrochemical column flow cell
• A novel green system for the electrochemical oxidation of alcohols is demonstrated using a column flow cell. Voltammetric analysis revealed that the oxidation of 1-phenylethanol and benzaldehyde are promoted by using both an Au-electrode and an alkaline medium. To conduct such reaction with a column flow cell, we developed a method to modify a carbon-fiber thread with Au nanoparticles. The column carbon-fiber thread electrode modified with Au nanoparticles showed a high surface area, enabling the efficient electrochemical oxidation of various alcohols.
• Suga, Tatsuya,Shida, Naoki,Atobe, Mahito

• (2021/02/09)
• 

• Rapid, chemoselective and mild oxidation protocol for alcohols and ethers with recyclable N-chloro-N-(phenylsulfonyl)benzenesulfonamide
• Chlorine is the 20th most abundant element on the earth compared to bromine, iodine, and fluorine, a sulfonimide reagent, N-chloro-N-(phenylsulfonyl)benzenesulfonamide (NCBSI) was identified as a mild and selective oxidant. Without activation, the reagent was proved to oxidize primary and secondary alcohols as well as their symmetrical and mixed ethers to corresponding aldehydes and ketones. With recoverable PS-TEMPO catalyst, selective oxidation over chlorination of primary and secondary alcohols and their ethers with electron-donating substituents was achieved. The reagent precursor of NCBSI was recovered quantitatively and can be reused for synthesizing NCBSI.
• Badani, Purav,Chaturbhuj, Ganesh,Ganwir, Prerna,Misal, Balu,Palav, Amey
• supporting information

  (2021/06/03)
• 

• A Synergistic Magnetically Retrievable Inorganic-Organic Hybrid Metal Oxide Catalyst for Scalable Selective Oxidation of Alcohols to Aldehydes and Ketones
• Herein, we report a synergistic silica coated magnetic Fe3O4 catalyst functionalized with nitrogen rich organic moieties and immobilized with cobalt metal ion (FNP-5) for selective oxidation of alcohols to aldehydes and ketones using tert-butyl hydroperoxide (TBHP) as oxidant. The catalyst was rigorously characterized via several techniques which delineate its core-shell structure, magnetic behavior, phase and crystal structure. The Co(III) acts as the active catalytic center for selective oxidation reaction. The control reactions revealed radical mechanistic pathway assisted by the synergism induced by the inorganic-organic hybrid nature of FNP-5. The other features of current protocol involve neat reaction conditions, high TOF values, scalability of product and low E-factor value (1.92). Moreover, FNP-5 could be effortlessly separated via an external magnet, displays recyclability over eight catalytic cycles and exhibits structural integrity even after rigorous use. Overall, these results manifest the understanding of synergistic architectures as sustainable surrogates for selective oxidation reactions.
• Mittal, Rupali,Awasthi, Satish Kumar

• p. 4799 - 4813

  (2021/09/30)
• 

• Zwitterion-induced organic-metal hybrid catalysis in aerobic oxidation
• In many metal catalyses, the traditional strategy of removing chloride ions is to add silver salts via anion exchange to obtain highly active catalysts. Herein, we reported an alternative strategy of removing chloride anions from ruthenium trichloride using an organic [P+-N-] zwitterionic compound via multiple hydrogen bond interactions. The resultant organic-metal hybrid catalytic system has successfully been applied to the aerobic oxidation of alcohols, tetrahydroquinolines, and indolines under mild conditions. The performance of zwitterion is far superior to that of many other common Lewis bases or Br?nsted bases. Mechanistic studies revealed that the zwitterion triggers the dissociation of chloride from ruthenium trichloride via nonclassical hydrogen bond interaction. Preliminary studies show that the zwitterion is applicable to catalytic transfer semi-hydrogenation.
• Hu, Rong-Bin,Lam, Ying-Pong,Ng, Wing-Hin,Wong, Chun-Yuen,Yeung, Ying-Yeung

• p. 3498 - 3506

  (2021/04/07)
• 

• The dehydrogenative oxidation of aryl methanols using an oxygen bridged [Cu-O-Se] bimetallic catalyst
• Herein, we report a new protocol for the dehydrogenative oxidation of aryl methanols using the cheap and commercially available catalyst CuSeO3·2H2O. Oxygen-bridged [Cu-O-Se] bimetallic catalysts are not only less expensive than other catalysts used for the dehydrogenative oxidation of aryl alcohols, but they are also effective under mild conditions and at low concentrations. The title reaction proceeds with a variety of aromatic and heteroaromatic methanol examples, obtaining the corresponding carbonyls in high yields. This is the first example using an oxygen-bridged copper-based bimetallic catalyst [Cu-O-Se] for dehydrogenative benzylic oxidation. Computational DFT studies reveal simultaneous H-transfer and Cu-O bond breaking, with a transition-state barrier height of 29.3 kcal mol?1
• Choudhury, Prabhupada,Behera, Pradyota Kumar,Bisoyi, Tanmayee,Sahu, Santosh Kumar,Sahu, Rashmi Ranjan,Prusty, Smruti Ranjita,Stitgen, Abigail,Scanlon, Joseph,Kar, Manoranjan,Rout, Laxmidhar
• supporting information

  p. 5775 - 5779

  (2021/04/12)
• 

• Chemoselective and ligand-free aerobic oxidation of benzylic alcohols to carbonyl compounds using alumina-supported mesoporous nickel nanoparticle as an efficient recyclable heterogeneous catalyst
• An economically efficient and operationally simple ligand-free protocol for the chemoselective oxidation of benzylic alcohols to carbonyl compounds has been developed using alumina-supported nickel nanoparticles as a stable recyclable heterogeneous catalyst along with potassium tert-butoxide in the presence of aerial oxygen as an eco-friendly oxidant. The aliphatic alcohols remained unaffected under the present condition. Excellent chemoselectivity has also been demonstrated through intermolecular and intramolecular competition experiments. This protocol accommodates a diverse range of substituents with the tolerance of various sensitive moieties during the reaction. The catalyst could be recovered by filtration and reused consecutively without any significant loss in the catalytic activity. Moreover, the heterogeneity of the catalyst has also been established by the “hot filtration method (Sheldon's test)”.
• Das, Asit Kumar,Nandy, Sneha,Bhar, Sanjay

• (2021/05/10)
• 

• Method for preparing carbonyl compound by oxidizing alcohol
• The invention provides a method for preparing aldehyde or ketone by alcohol oxidation. Iron nitrate hydrate (Fe (NO) is used as a solvent. 3 )3 · 992 O). 4 - Hydroxyl -2, 2, 6, 6 - tetramethylpiperidine oxide (4 - OH-TEMPO) and carboxylic acid are catalysts, and the alcohol is oxidized to aldehydes or ketones with oxygen or air as an oxidizing agent. Compared with the prior art, water serves as a solvent, so that the pollution-free halogenated hydrocarbon or strong carcinogenic sodium nitrite (NaNO) is avoided. 2 The method is green and environment-friendly, the cost is greatly reduced, and the method is a method suitable for industrial production.
• -
• Paragraph 0029

  (2021/09/08)
• 

• PhIO-Mediated oxidative dethioacetalization/dethioketalization under water-free conditions
• Treatment of thioacetals and thioketals with iodosobenzene in anhydrous DCM conveniently afforded the corresponding carbonyl compounds in high yields under water-free conditions. The mechanistic studies indicate that this dethioacetalization/dethioketalization process does not need water and the oxygen of the carbonyl products comes from the hypervalent iodine reagent.
• Du, Yunfei,Ouyang, Yaxin,Wang, Xi,Wang, Xiaofan,Yu, Zhenyang,Zhao, Bingyue,Zhao, Kang

• p. 48 - 65

  (2021/06/16)
• 

• An Effective and Inexpensive Hf/ZSM-5 Catalyst for Efficient HMF Formation from Cellulose
• Abstract: The production of 5-hydroxymethylfurfural (HMF) from cellulose is of great significance for the high-value utilization of biomass, although this route currently faces the challenge of low efficiency. In the present work, a series of effective (x)Hf/ZSM-5 catalysts were developed for HMF production from cellulose, and analyzed by BET, XRD, SEM, ICP, NH3-TPD, Py-FTIR techniques. Driven by the (5)Hf/ZSM-5 catalyst, HMF with a yield of up to 67.5% and 17.2% of furfural are simultaneously obtained from cellulose in the H2O(NaCl)/THF biphasic system. Moreover, after four consecutive cycles, (5)Hf/ZSM-5 catalyst still maintained part of its catalytic activity. The 67.5% HMF yield achieved herein is one of the highest yields achieved in the conversion reaction using cellulose as a substrate, and the catalytic performance of the H2O(NaCl)/THF system containing the (5)Hf/ZSM-5 catalyst is even comparable to that of the expensive ionic liquid system. This result reflects the application prospect of (5)Hf/ZSM-5 catalyst in the future industrial production process of HMF. Graphic Abstract: [Figure not available: see fulltext.]
• Wu, Ningxin,Zhang, Manling,Pan, Xiaomei,Zhang, Jin,Gao, Lijing,Xiao, Guomin

• p. 1984 - 1992

  (2020/11/09)
• 

• Comparative account of catalytic activity of Ru- and Ni-based nanocomposites towards reductive amination of biomass derived molecules
• This work includes an effective comparison of metallic ruthenium and nickel nanoparticles loaded on montmorillonite clay (MMT) for reductive amination reaction of biomass-derived molecules. It comprises an eco-friendly reaction using water as a solvent, utilizing molecular hydrogen and liquor ammonia (25% aq. solution) for the synthesis of primary amines from bio-derived aldehydes within 3–10 h of reaction time. Various parameters such as temperature, hydrogen pressure, substrate/ammonia concentration ratio, and reaction time were optimized while comparing the selectivity of primary amines for both catalysts. The applicability scope of these catalysts was explored with a library of aryl and heterocyclic aldehydes. The reductive amination of crude furfural extracted from biomass feedstock (rice husk) and pure xylose sugar was tested, showing yields in the range of 11–36%, to show the wider industrial scope of both nanocomposites. Gram scale conversion was also carried out to showcase the bulk scalability of the Ru/MMT catalyst.
• Bhanage, Bhalchandra M.,Gokhale, Tejas A.,Raut, Amol B.

• (2021/06/18)
• 

• Acceptorless Photocatalytic Dehydrogenation of Furfuryl Alcohol (FOL) to Furfural (FAL) and Furoic Acid (FA) over Ti3C2Tx/CdS under Visible Light
• Acceptorless photocatalytic dehydrogenation is not only a promising alternative to photocatalytic water splitting for hydrogen generation but also provides a green and sustainable strategy for the synthesis of value-added organic compounds. In this work, Ti3C2Tx/CdS nanocomposites were obtained by self-assembly of hexagonal CdS in the presence of preformed Ti3C2Tx nanosheets, which serves as a photocatalyst for acceptorless dehydrogenation of biomass-derived furfuryl alcohol (FOL) to furfural (FAL) and furoic acid (FA) in neutral and alkaline medium respectively, with simultaneous generation of stoichiometric hydrogen under visible light. Ti3C2Tx MXene acts as an efficient cocatalyst for the photocatalytic dehydrogenation of FOL over CdS, with an optimum performance achieved over 0.50 wt%Ti3C2Tx/CdS nanocomposite. This study provides an economic and sustainable strategy for the simultaneous valorization of biomass-derived FOL to produce FAL and FA as well as the production of clean energy hydrogen under mild condition based on noble metal-free semiconductor-based photocatalysts.
• Wang, Jiaqi,Liu, Xinyu,Li, Zhaohui

• p. 2932 - 2938

  (2021/08/20)
• 

• Niobium phosphates as bifunctional catalysts for the conversion of biomass-derived monosaccharides
• The direct conversion of glucose and xylose into HMF and furfural is more efficient using a combination of Lewis and Br?nsted acids. Herein, niobium phosphates were prepared with different compositions, which affect its surface acidity and, consequently, the catalytic activity. The catalysts with a high P/Nb molar ratio presented a low molar ratio between Lewis and Br?nsted acid sites (L/B ratio), while those with low P/Nb molar ratio displayed a high L/B ratio. NbP-2, the sample with the highest L/B ratio, showed the highest reaction rate for both HMF and furfural formation. It was found, indeed, that the reaction rate for monosaccharides conversion and furans formation correlate linearly with the L/B ratio. The results presented not only introduce niobium phosphates with a high L/B molar ratio as promising catalysts for HMF and furfural production but also provide fundamental knowledge that will guide the design of other bifunctional heterogeneous catalysts.
• Vieira, José Lucas,Paul, Geo,Iga, Gustavo D.,Cabral, Natalia M.,Bueno, José Maria C.,Bisio, Chiara,Gallo, Jean Marcel R.

• (2021/03/30)
• 

• DIBALH: From known fundamental to an unusual reaction; Chemoselective partial reduction of tertiary amides in the presence of esters
• This study presents a quick and reliable approach to the chemoselective partial reduction of tertiary amides to aldehydes in the presence of readily reducible ester groups using commercial DIBALH reagent. Moreover, the developed method was also extended to multi-functional molecules bearing ester moieties, which were successfully chemoselectively reduced to the corresponding aldehydes. This journal is
• An, Duk Keun,Heo, Yu Jin,Jaladi, Ashok Kumar,Kim, Hyun Tae

• p. 33809 - 33813

  (2021/12/09)
• 

• Samarium-based Grignard-type addition of organohalides to carbonyl compounds under catalysis of CuI
• Grignard-type additions were readily achieved under the mediation of CuI (10 mol%) and samarium (2 equiv.) by employing various organohalides,e.g.benzyl, aryl, heterocyclic and aliphatic halides (Cl, Br or I), and diverse carbonyl compounds (e.g.carbonic esters, carboxylic esters, acid anhydrides, acyl chlorides, ketones, aldehydes, propylene epoxides and formamides) to afford alcohols, ketones and aldehydes, respectively, with high efficiency and chemoselectivity, in which the organosamarium intermediate might be involved.
• Liu, Chen,Liu, Yongjun,Qi, Yan,Song, Bin,Wang, Liang,Xiao, Shuhuan
• supporting information

  p. 6169 - 6172

  (2021/06/30)
• 

• Feasible synthesis of bifurfural from renewable furfural derived 5-bromofurfural for polymerization
• Deriving versatile monomers from bulky biomass for polymer production can greatly replace fossil resources as the carbon source of chemical industry. The present studies introduce the feasible synthesis of bifurfural, a bifunctionalized bifuran monomer, from the furfural platform. The reaction was carried out through reductive coupling of 5-bromofurfural with CO as the reductant source with commercial Pd/C as the catalyst under gentle conditions, and the catalyst is recyclable and reusable. So prepared bifurfural was preliminarily investigated as a monomer for poly(Schiff base) material synthesis, and it was found that the poly(Schiff base) derived from nonlinear bifurfural monomer polymerizing with linear p-phenylenediamine demonstrated larger surface area than that from petrochemical 4,4′-biphenyldicarboxaldehyde with excellent thermal stability, thus offering a new opportunity in bifurfural based furfural utilization in polymer industry.
• Chen, Zhuqi,Lei, Yu,Liao, Yonggui,Yin, Guochuan,Zhu, Jinlian

• (2021/08/16)
• 

• A Magnetically Recyclable Palladium-Catalyzed Formylation of Aryl Iodides with Formic Acid as CO Source: A Practical Access to Aromatic Aldehydes
• A magnetically recyclable palladium-catalyzed formylation of aryl iodides under CO gas-free conditions has been developed by using a bidentate phosphine ligand-modified magnetic nanoparticles-anchored- palladium(II) complex [2P-Fe 3O 4@SiO 2-Pd(OAc) 2] as catalyst, yielding a wide variety of aromatic aldehydes in moderate to excellent yields. Here, formic acid was employed as both the CO source and the hydrogen donor with iodine and PPh 3as the activators. This immobilized palladium catalyst can be obtained via a simple preparative procedure and can be facilely recovered simply by using an external magnetic field, and reused at least 9 times without any apparent loss of catalytic activity.
• You, Shengyong,Zhang, Rongli,Cai, Mingzhong

• p. 1962 - 1970

  (2021/01/25)
• 

• A Combined Experimental–Theoretical Study on Diels-Alder Reaction with Bio-Based Furfural: Towards Renewable Aromatics
• The synthesis of relevant renewable aromatics from bio-based furfural derivatives and cheap alkenes is carried out by using a Diels-Alder/aromatization sequence. The prediction and the control of the ortho/meta selectivity in the Diels-Alder step is an important issue to pave the way to a wide range of renewable aromatics, but it remains a challenging task. A combined experimental-theoretical approach reveals that, as a general trend, ortho and meta cycloadducts are the kinetic and thermodynamic products, respectively. The nature of substituents, both on the dienes and dienophiles, significantly impacts the feasibility of the reaction, through a modulation on the nucleo- and electrophilicity of the reagents, as well as the ortho/meta ratio. We show that the ortho/meta selectivity at the reaction equilibrium stems from a subtle interplay between charge interactions, favoring the ortho products, and steric interactions, favoring the meta isomers. This work also points towards a path to optimize the aromatization step.
• van Scodeller,De Oliveira Vigier, Karine,Muller, Eric,Ma, Changru,Guégan, Frédéric,Wischert, Raphael,Jér?me, Fran?ois

• p. 313 - 323

  (2020/10/19)
• 

• Photo-on-Demand Synthesis of Vilsmeier Reagents with Chloroform and Their Applications to One-Pot Organic Syntheses
• The Vilsmeier reagent (VR), first reported a century ago, is a versatile reagent in a variety of organic reactions. It is used extensively in formylation reactions. However, the synthesis of VR generally requires highly toxic and corrosive reagents such as POCl3, SOCl2, or COCl2. In this study, we found that VR is readily obtained from a CHCl3 solution containing N,N-dimethylformamide or N,N-dimethylacetamide upon photo-irradiation under O2 bubbling. The corresponding Vilsmeier reagents were obtained in high yields with the generation of gaseous HCl and CO2 as byproducts to allow their isolations as crystalline solid products amenable to analysis by X-ray crystallography. With the advantage of using CHCl3, which bifunctionally serves as a reactant and a solvent, this photo-on-demand VR synthesis is available for one-pot syntheses of aldehydes, acid chlorides, formates, ketones, esters, and amides.
• Liang, Fengying,Eda, Kazuo,Okazoe, Takashi,Wada, Akihiro,Mori, Nobuaki,Konishi, Katsuhiko,Tsuda, Akihiko

• p. 6504 - 6517

  (2021/05/06)
• 

• Iodine-catalyzed alcohol disproportionation method
• The invention relates to the technical field of catalysis, in particular to an iodine-catalyzed alcohol disproportionation method which comprises the following steps: sequentially adding alcohol, iodine and a solvent into a high-temperature and high-pressure reaction kettle, introducing a certain amount of nitrogen, conducting reacting for a certain time, collecting an organic phase after the reaction is ended, and conducting fractionating to obtain corresponding alkane and aldehyde/ketone. Alcohol disproportionation is efficient and atom-economical conversion without any additional oxidizing agent and reducing agent, and hydrocarbon and aldehyde/ketone molecules which are easy to separate can be formed at the same time. Meanwhile, the method has wide functional group tolerance, various substrate samples including aryl alcohol derivatives, heterocyclic alcohol derivatives, allyl alcohol derivatives and dihydric alcohol are tested, and the result shows that most of the substrate samples show good or extremely good yield.
• -
• Paragraph 0030-0031

  (2021/06/13)
• 

• Method for preparing aldehyde compounds by oxidative cleavage of carbon-carbon bonds of terminal alkene compounds
• The invention discloses a method for preparing aldehyde compounds by oxidizing and breaking carbon-carbon bonds of terminal alkene compounds. The method comprises the following steps: adding an alkene-terminated compound, an additive and a nitrogen-doped mesoporous carbon-loaded monatomic catalyst into a fatty primary alcohol solvent, putting into a pressure container, sealing, introducing oxygen source gas with a certain pressure, controlling the pressure of the oxygen source gas to be 0.1-1MPa and the reaction temperature to be 80-150 DEG C, and obtaining a reaction product, namely the aldehyde compound. The nitrogen-doped mesoporous carbon-loaded monatomic catalyst adopted by the invention is high in activity, the highest separation yield of the aldehyde compound as a reaction product reaches 99%, the method is wide in application range, the reaction conditions are easy to control, the catalyst can be recycled, the post-treatment is simple, and the method is suitable for industrial production.
• -
• Paragraph 0077-0078; 0089-0090

  (2021/06/06)
• 

• Conversion of glucose to levulinic acid and upgradation to γ-valerolactone on Ru/TiO2catalysts
• Combining glucose dehydration and the subsequent hydrogenation in one pot is a preferable approach for process development as such a method allows in situ generation of the reactive intermediate to undergo further reaction without extra energy-intensive separation. Herein, phosphotungstic acid and various types of titania (anatase, rutile, P25) supported Ru-based catalysts were considered as the dehydration and hydrogenation catalysts, respectively. Modulating the different reactant media (N2, H2), various products were obtained with GBL-H2O as the solvent. A considerable yield (42%) of levulinic acid (LA) and γ-valerolactone (GVL) (40%) were obtained in nitrogen and subsequent hydrogen. Ru/TiO2 (rutile) was the favorable hydrogenation catalyst among the three types of Ru/TiO2. Meanwhile, a certain amount of sorbitol (36%) was obtained in pure hydrogen. The hydrogenation of glucose is more likely to occur than the glucose dehydration. The physicochemical properties of the catalysts were characterized by XRD, BET, TPR, STEM and in situ CO/FT-IR, and the results show that well-dispersed Ru particles are located on the rutile crystallites, which facilitated the hydrogenation of LA. A strong metal support interaction (SMSI) was responsible for the various microstructure properties and the different hydrogenation reactivity. This work allows a better understanding of the reaction paths of glucose conversion.
• Ding, Guoqiang,Liu, Yubo,She, Haohao,Yang, Yong,Zhao, Guoping,Zhu, Yulei

• p. 14406 - 14413

  (2021/08/23)
• 

• Tin, molybdenum and tin-molybdenum oxides: Influence of Lewis and Bronsted acid sites on xylose conversion
• In this study, tin oxide (SnO2), molybdenum oxide (MoO3) and a mixed oxide based on tin and molybdenum (respectively, Sn100, Mo100 and SnMo25, synthesized by the impregnation method) were applied in xylose conversion. The best results were obtained employing Mo100 and SnMo25. In the presence of SnMo25, after 0.5 h, xylose conversions of 39.5%, 34.1% and 63.4% were obtained, respectively, at 110, 130 and 150 °C. For Mo100, conversions of 49.6%, 71.8% and 85.3% were attained under the same reaction conditions, showing that Mo100 provided the best conversion results. However, with the use of this catalyst there was an increase in the amount of soluble and insoluble polymeric material. In terms of the soluble products formed from xylose, depending on the reaction condition were detected xylulose (X), lyxose (L) and furfural (FUR), glyceraldehyde (GL), pyruvaldehyde (PYR), glycoaldehyde (GLYC), dihydroxyacetone (DHA), lactic acid (AL), levulinic acid (LA) and acetic acid (AA). However, with the use of Sn100 or without a catalyst (systems with low conversions) there was mainly the formation of lyxose. The use of Mo100 and SnMo25 (systems which exhibit high acidity) leads mainly to isomerization, epimerization and dehydration reactions, as in the case of the retro-aldol pathway and furfural conversion, highlighting the importance of Lewis and Bronsted acid sites in relation to modulating the selectivity of the systems.
• Meneghetti, Mario R.,Meneghetti, Simoni M. P.,Pryston, Dhara B. A.,da Silva Avelino, Débora Olimpio,dos Santos, Thatiane V.

• (2021/11/16)
• 

• Conversion of saccharides in enteromorpha prolifera to furfurals in the presence of FeCl3
• In this work, the conversion of saccharides in Enteromorpha prolifera (E. prolifera) in the presence of a series of metal chloride was studied. FeCl3, was found the best precursor of catalyst for obtaining furfural products, with 8.9 wt% 5-hydroxymethylfurfural (HMF), 14.9 wt% 5-methylfurfural (5-MF), and 4.2 wt% 2-formylfuran (FF) without levulinic acid (LA) formation, under the optimized reaction conditions (190 °C, 60 min and 0.0125 mol/L FeCl3 loading). In H2O-THF-NaCl bi-solvent system catalyzed by FeCl3 derived species, the highest yields of furfurals (20.0 wt% HMF, 19.8 wt% 5-MF, and 5.2 wt% FF) could be obtained when 2 wt% NaCl was added. With the help of THF by in situ extraction, nearly 90 % of the furfural products was enriched in the THF phase, while H2O had a great contribution to the dissolution and hydrolysis of polysaccharides. The catalytic activity and product selectivity of FeCl3 for the conversion of other saccharide model compounds were also studied comparatively. In the presence of FeCl3, the hexose model compounds were converted to LA, whereas those in E. prolifera to HMF. It was found that FeCl3 might interact with the saccharides from E. prolifera to form new species, which could catalyze the conversion of hexose to HMF without LA generation. The new species was considered as a kind of complexes containing Fe(II), which suppressed the rehydration decomposition of HMF. This work provided an effective method for the production of value-added chemicals from E. prolifera.
• Chen, Yaguang,Zhou, Yingdong,Zhang, Rui,Hu, Changwei

• (2019/12/24)
• 

• METHOD OF FORMING MONOMERS AND FURFURAL FROM LIGNOCELLULOSE
• The present disclosure relates to a method of producing monophenolicmonomers and furfural from lignocellulosic biomass beating the biomass in a solvent together with a zeolite based catalyst.
• -
• Page/Page column 19; 20; 25

  (2020/06/05)
• 

• Production of furfural from xylose catalyzed by a novel calcium gluconate derived carbon solid acid in 1,4-dioxane
• A novel carbon-based solid acid catalyst (SC-GCa-800) was prepared by the carbonization of calcium gluconate at high-temperature followed by sulfonation with 4-diazoniobenzenesulfonate at room temperature. The catalyst was characterized by FT-IR, XPS, TEM, SEM, TGA, N2 adsorption-desorption and elemental analysis to reveal its physical and chemical properties. Furthermore, the effects of reaction temperature, retention time, substrate concentration, catalyst loading and solvent types were investigated. It was demonstrated that SC-GCa-800 is an efficient solid acid catalyst for furfural production obtained from xylose in 1,4-dioxane. A 76.9% furfural yield can be achieved from 100 mg xylose at 140 °C in 40 min by using a 50 mg catalyst. The catalyst showed high stability and could be recycled five times without a significant loss of catalytic activity. The results indicated that the high catalytic activity of SC-GCa-800 was dependent on its high acidity, BET surface and pore structure. More importantly, the furfural can be obtained at low temperature (100-140 °C) and separated easily from the solvent due to the low boiling point of 1,4-dioxane.
• Li, Wenzhi,Liu, Minghou,Liu, Yang,Su, Mingxue,Yang, Tao
• supporting information

  p. 7968 - 7975

  (2020/06/10)
• 

• Magnetic Fe3O4 nanoparticles as easily separable catalysts for efficient catalytic transfer hydrogenation of biomass-derived furfural to furfuryl alcohol
• Magnetic Fe3O4-12 nanoparticles, an easily separable heterogeneous catalyst, exhibits high catalytic performance in the catalytic transfer hydrogenation (CTH) reaction of biomass-derived furfural (FAL) to furfuryl alcohol (FOL) with 2-propanol (2-PrOH) as the hydrogen source (90.1 percent FOL yield at 160 °C for 5 h). Comparing Fe3O4 nanoparticles with different particle sizes found that the smaller the nanoparticles, the larger the BET surface area, pore volume and pore diameter, resulting in more acid-base active sites through BET, SEM, TEM, NH3-/CO2-TPD and other characterizations. Moreover, a scaled-up CTH experiment of FAL and a stepwise reaction from xylose to FOL verified that the catalytic system has great industrial application prospects. A feasible flowchart of the chemical process from xylose to FOL was designed, which can realize the regeneration of biomass resources (xylose derived from corncob), the reuse and recycling of catalysts and solvents, and minimize the amount of solvents and pollutant emissions.
• Cao, Jingjie,Feng, Shouhua,Hou, Pan,Liu, Hui,Ma, Mingwei,Tian, Ge,Yue, Huijuan,Zhang, Peng

• (2020/07/07)
• 

• The Promotion Effect of NaCl on the Conversion of Xylose to Furfural?
• In this work, the promotion effect of NaCl on the conversion of xylose to furfural in H2O was studied. It was found that xylose conversion and furfural yield increased with NaCl concentration. NaCl decreased the pH of the solution providing H+ for the acid catalytic dehydration of xylose. The formation of oligomers was determined by GPC and ESI-MS in the initial stage of reaction, especially at low temperature. Excess NaCl promoted the formation of humins in the late stage of the reaction. NaCl could also change the decomposition route of formic acid. Meanwhile, NaCl had the ability of phase separation. Combining these effects with organic solvent during the reaction could inhibit the formation of humins and increase the yield of furfural. In NaCl-H2O-THF biphasic system without other catalyst, the optimal furfural yield of 76.7% and selectivity of 77.6% were achieved at 463 K in 2 h.
• Fang, Qianying,Hu, Changwei,Jiang, Zhicheng,Li, Zheng,Luo, Yiping

• p. 178 - 184

  (2020/01/28)
• 

• Roles of acidic sites in alumina catalysts for efficient d-xylose conversion to lactic acid
• This work investigated the conversion of d-xylose to lactic acid over heterogeneous Al2O3 and ZSM-5 catalysts in aqueous solution. γ-Al2O3, an abundant low cost catalyst, exhibited superior lactic acid yield (63 mol%) at 170 °C, compared to α-Al2O3, ZSM-5 catalysts and the reported data in the literature so far. Our experiment suggested that the outstanding lactic acid yield could be attributed to the large specific surface area and the abundance of Lewis acid sites in γ-Al2O3. In contrast, furfural selectivity was significantly promoted in the catalyst free system and the ZSM-5 catalyst, which has abundant Br?nsted acid sites, but lacks Lewis acid sites. The theoretical part revealed that reactive Lewis acid sites in γ-Al2O3 and the solvent play important roles in the C-C bond activation and thermodynamic stability of the d-xylose to lactic acid pathway. The green catalytic system proposed in this work shows great potential as an alternative method for lactic acid production for future industrial application. This journal is
• Kiatphuengporn, Sirapassorn,Junkaew, Anchalee,Luadthong, Chuleeporn,Thongratkaew, Sutarat,Yimsukanan, Chakrit,Songtawee, Siripit,Butburee, Teera,Khemthong, Pongtanawat,Namuangruk, Supawadee,Kunaseth, Manaschai,Faungnawakij, Kajornsak

• p. 8572 - 8583

  (2020/12/31)
• 

• A Strategy for Accessing Aldehydes via Palladium-Catalyzed C?O/C?N Bond Cleavage in the Presence of Hydrosilanes
• We report the catalytic reduction of both active esters and amides by selective C(acyl)?X (X=O, N) cleavage to access aldehyde functionality via a palladium-catalyzed strategy. Reactions are promoted by hydrosilanes as reducing reagents with good to excellent yields and with excellent chemoselectivity for C(acyl)?N and C(acyl)?O bond cleavage. Carboxylic acid C(acyl)?O bonds are activated by 2-chloro-4,6-dimethoxy-1,3,5-triazine (CDMT) to form triazine ester intermediates, which further react with hydrosilanes to yield aldehydes in one-pot two-step procedures. We demonstrate that C(acyl)?O cleavage/formylation offers higher yields and broader substrate scopes compared with C(acyl)?N cleavage under the same reaction conditions.
• He, Zhanyu,Liu, Tingting,Ru, Junxiang,Wang, Yulin,Wang, Zijia,Zeng, Zhuo

• p. 5794 - 5800

  (2020/12/01)
• 

• 9,10-Dihydroanthracene auto-photooxidation efficiently triggered photo-catalytic oxidation of organic compounds by molecular oxygen under visible light
• The development of mild and efficient process for the selective oxidation of organic compounds by molecular oxygen (O2) can be one of the key technologies for synthesizing oxygenates. This paper discloses an efficient and mild synthesis protocol for the O2-involved ethylbenzene (EB) photooxidation triggered by 910-dihydroanthracene (DHA) auto- photooxidation in acetone under visible light illumination, which can achieve 87.7 percent EB conversion and 99.5 percent acetylacetone (ACP) selectivity under ambient conditions. Also, 62.9 percent EB conversion and 96.3 percent ACP selectivity is obtained in air atmosphere. Furthermore, this protocol has a good adaptability for the photooxidation of other organic substrates such as tetrahydronaphthalene, diphenylmethane, toluene, cyclohexane, cyclohexene, alcohol, methylfuran and thioether to their corresponding oxygenates. A series of control and quenching tests, combined with EPR spectra, suggest that the photo-excited DHA can transfer its photo-electron to O2 to yield a superoxide radical anion (O2??), then DHA is preferentially oxidized to anthraquinone (AQ) by the active O2?? owing to its high reactivity. Finally, the in situ generated AQ as an active photo-catalyst can achieve the photooxidation of EB and other organic compounds by O2. The present photo-autoxidation protocol gives a good example for the O2-based selective oxidation of inert hydrocarbons under mild conditions.
• Chen, Mengke,Deng, Youer,Fu, Zaihui,Hu, Wenwei,Jiang, Dabo,Liu, Yachun,Mao, Feng,Su, Anqun,Yang, Bo,Zhang, Chao

• (2020/08/11)
• 

• High catalytic performance of the first electrospun nano-biohybrid, Mn3O4/copper complex/polyvinyl alcohol, from Amaranthus spinosus plant for biomimetic oxidation reactions
• In this study, a novel nano-biocomposite, polyvinylalcohol/Mn3O4/water-soluble copper complex (PVA/Mn3O4/CuWSC), was produced from Amaranthus spinosus. By combining water-soluble copper nanocomplex and Mn3O4 nanoparticles along with polyvinyl alcohols and extracts of this plant, this bio nanomaterial was prepared via electrospinning process. This nanohybrid was characterized using transmission electron microscopy, scanning electron microscopy, atomic force microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and elemental analysis. Based on its catalytic activities, it is considered a heterogeneous catalyst and is used for the oxidation of alcohols in industrial reactions. It can oxidize the primary and secondary alcohols to corresponding aldehyde and ketone products with high yield and excellent selectivity using H2O2 under solvent-free conditions. The recyclability and reusability of PVA/Mn3O4/CuWSC show that it can be a promising catalyst for clean industrial catalytic applications.
• Ekrami-Kakhki, Mehri-Saddat,Naeimi, Atena

• (2020/02/05)
• 

• Amorphous Nickel Phosphide Nanoparticles for Selective Hydrogenation of Cinnamaldehyde
• Abstract: The selective hydrogenation of α,β-unsaturated aldehydes plays a crucial role in industrial production, and an efficient non-noble metal catalyst for it has been pursued to reduce the cost. Herein, we report an amorphous nickel phosphide for the selective hydrogenation of cinnamaldehyde. Compared to crystalline nickel phosphide, amorphous nickel phosphide showed both high activity and high selectivity to target products. Its catalytic performance was also better than that of commercial Pd/C catalyst. In addition, initial P/Ni ratio was found to be an important factor to affect the activity of amorphous nickel phosphide. High initial P/Ni ratio led to high activity owing to small particles, high surface area and strong metallicity of as-synthesized catalyst. Moreover, excellent catalytic performances of amorphous nickel phosphide were observed in the selective hydrogenation of different α,β-unsaturated aldehydes and ketones. Graphic Abstract: [Figure not available: see fulltext.].
• Liu, Ping,Zhu, Ya-Lu,Zhou, Lei,Zhang, Wei-Hong,Li, Yong-Xin

• p. 2695 - 2702

  (2020/03/23)
• 

• Oxidation of alcohols using an oxoammonium salt bearing the nitrate anion
• A methodology for the oxidation of alcohols to the corresponding carbonyl compounds is reported using a sub-stoichiometric quantity of an oxoammonium salt bearing the nitrate counterion. The approach proves successful for the oxidation of a range of alcohol substrates including those bearing an oxygen atom β to the site of oxidation or an α-trifluoromethyl moiety. The mechanism of the reaction has been probed and also gives an insight into the previously reported nitric acid mediated oxidation of alcohols.
• Miller, Shelli A.,Sandoval, Arturo León,Leadbeater, Nicholas E.
• supporting information

  (2019/12/25)
• 

• Flavin Nitroalkane Oxidase Mimics Compatibility with NOx/TEMPO Catalysis: Aerobic Oxidization of Alcohols, Diols, and Ethers
• Biomimetic flavin organocatalysts oxidize nitromethane to formaldehyde and NOx - providing a relatively nontoxic, noncaustic, and inexpensive source for catalytic NO2 for aerobic TEMPO oxidations of alcohols, diols, and ethers. Alcohols were oxidized to aldehydes or ketones, cyclic ethers to esters, and terminal diols to lactones. In situ trapping of NOx and formaldehyde suggest an oxidative Nef process reminiscent of flavoprotein nitroalkane oxidase reactivity, which is achieved by relatively stable 1,10-bridged flavins. The metal-free flavin/NOx/TEMPO catalytic cycles are uniquely compatible, especially compared to other Nef and NOx-generating processes, and reveal selectivity over flavin-catalyzed sulfoxide formation. Aliphatic ethers were oxidized by this method, as demonstrated by the conversion of (-)-ambroxide to (+)-sclareolide.
• Thapa, Pawan,Hazoor, Shan,Chouhan, Bikash,Vuong, Thanh Thuy,Foss, Frank W.

• p. 9096 - 9105

  (2020/08/14)
• 

• Magnetic nanoparticle supported ionic liquid phase catalyst for oxidation of alcohols
• Anew magnetic nanoparticle supported ionic liquid phase (SILP) catalyst containing perruthenate anions was prepared by a multistep procedure. The various analytical techniques such as FT-IR spectroscopy, X-ray photoelectron spectroscopy, transmission elec
• Naikwade, Altafhusen,Jagadale, Megha,Kale, Dolly,Rashinkar, Gajanan

• p. 1088 - 1097

  (2020/10/20)
• 

• Visible-light mediated facile dithiane deprotection under metal free conditions
• Visible light mediated facile and selective dithiane deprotection under metal free conditions is developed. Eosin Y (1 mol%) proved to be an effective catalyst for the dithiane deprotection under the ambient photoredox conditions. The standard household compact fluorescent light source (CFL bulb) proved to be effective under open-air conditions in aqueous acetonitrile at room temperature. The protocol that exhibits a broad substrate scope and functional group tolerance has been shown to expand to a range of transformations for the electron-rich and -deficient thioacetals and thioketals. The synthetic utility of this protocol has also been demonstrated by gram-scale application.
• Dharpure, Pankaj D.,Bhowmick, Anindita,Warghude, Prakash K.,Bhat, Ramakrishna G.

• (2019/12/09)
• 

• Catalytic Conversion of Glucose to 5-Hydroxymethylfurfural and Furfural by a Phosphate-Doped SnO2 Catalyst in γ-Valerolactone-Water System
• Abstract: 5-Hydroxymethylfurfural (5-HMF) and furfural are produced from glucose by using a novel phosphate-doped SnO2 catalyst in GVL/water system. Comparing with the low yield (19.3% 5-HMF, 7.2% furfural) of SnO2 as catalyst, the loading of 15 wt% phosphate on the SnO2 can enhance the yield of 5-HMF (39.2%) and furfural (12.5%) from glucose under same reaction conditions. Furthermore, under the optimal conditions, the results indicate that the phosphated SnO2 catalyst, which contains 5 wt% phosphate, can result in 46.4% yield of 5-HMF and 18.9% yield of furfural at 180 °C for 90 min. The phosphated SnO2 catalysts are characterized by using XRD, TEM, Py-IR, XPS and TPD to reveal their structural, surface, and acid properties. And the enhanced 5-HMF and furfural yield could be attributed to the higher acidity, and the incorporation of phosphate into the framework of SnO2. Graphic Abstract: [Figure not available: see fulltext.].
• Li, Wenzhi,Yang, Tao,Su, Mingxue,Liu, Yang

• p. 3304 - 3313

  (2020/05/04)
• 

• tert-Butanol intervention enables chemoselective conversion of xylose to furfuryl alcohol over heteropolyacids
• Both the solvent and catalyst play important roles in the chemoselective transformation of biomass-related compounds to fine chemicals and fuels. We report herein an innovative catalytic strategy for the direct valorization of xylose without external H2producing high yield of furfuryl alcohol (FA), which is a versatile platform molecule. The solventtert-butanol served not only as a precursor of the hydrogen honor, but also as a shield to facilitate xylose dehydration and inhibit the polymerization and decomposition reactions of FA. Commercial H4SiW12O40was found to work as a multifunctional catalyst during the cascade conversion and had good reusability. The underlying catalytic mechanism revealed that the Br?nsted and Lewis acid sites co-existed cooperatively to catalyze the xylose dehydration step and the active metal site of W atom adsorbed the hydrogen proton for the transfer hydrogenation of furfural to FA. After the incorporation of the formic acid as a supplemental hydrogen source, an unprecedented FA yield of 90% could be accomplished in a batch reactor under mild conditions. The kinetic behavior describing the conversion of xylose to FA was investigated to monitor the process. The estimated activation energies for xylose dehydration, furfural hydrogenation, and FA decomposition were 85.1, 78.8, and 101.1 kJ mol?1, respectively. This study opens a new avenue for the selective production of FA from hemicellulose-derived pentose in a green and straightforward manner.
• He, Liang,Li, Hui,Peng, Lincai,Wang, Juan,Wang, Mengmeng,Zhang, Junhua
• supporting information

  p. 5656 - 5665

  (2020/09/21)
• 

• Facile synthesis of a highly efficient Co/Cu@NC catalyst for base-free oxidation of alcohols to esters
• The direct oxidation of alcohols to esters is an environmentally benign and cost-effective organic synthetic strategy, but it is still a great challenge to discover an economic, highly active, and long-term stable catalyst for efficient transformation of alcohols to esters under milder conditions. Herein, we developed cobalt and copper nanoparticle -co-decorated nitrogen-doped carbon catalysts (CoCu@NCn) through two steps of ball milling and calcination. It was found that CoCu@NCn could catalyze the oxidation of alcohols to esters effectively in the absence of basic additives. The catalytic activity was much higher than those of monometallic Co@NC2 and Cu@NC2 samples, and the catalyst can be conveniently recovered and quite steadily reused. Through a series of control experiments and characterizations, it is concluded that the remarkable catalytic performance of CoCu@NC2 was associated with the synergistic effect between the two metal components, the enhanced basic active sites and the active surface area.
• Jiang, Jiusheng,Li, Xiang,Du, Shengyu,Shi, Langchen,Jiang, Pingping,Zhang, Pingbo,Dong, Yuming,Leng, Yan

• p. 7780 - 7785

  (2020/06/09)
• 

• P- and F-co-doped Carbon Nitride Nanocatalysts for Photocatalytic CO2 Reduction and Thermocatalytic Furanics Synthesis from Sugars
• A new P- and F-co-doped amorphous carbon nitride (PFCN) has been synthesized via sol-gel-mediated thermal condensation of dicyandiamide. Such synthesized P- and F-co-doped carbon nitride displayed a well-defined mesoporous nanostructure and enhanced visible light absorption region up to infrared with higher BET surface area of 260.93 m2 g?1; the highest recorded value for phosphorus-doped carbon nitride materials. Moreover, the formation mechanism is delineated and the role of templates was found to be essential not only in increasing the surface area but also in facilitating the co-doping of P and F atoms. Co-doping helped to narrow the optical band gap to 1.8 eV, thus enabling an excellent photocatalytic activity for the aqueous reduction of carbon dioxide into methanol under visible-light irradiation, which is fifteen times higher (119.56 μmol g?1 h?1) than the bare carbon nitride. P doping introduced Br?nsted acidity into the material, turning it into an acid-base bifunctional catalyst. Consequently, the material was also investigated for the thermal conversion of common carbohydrates into furanics.
• Kumar, Subodh,Gawande, Manoj B.,Kopp, Josef,Kment, Stepan,Varma, Rajender S.,Zbo?il, Radek

• p. 5231 - 5238

  (2020/09/21)
• 

• Visible-light assisted of nano Ni/g-C3N4 with efficient photocatalytic activity and stability for selective aerobic C?H activation and epoxidation
• A selective, economical, and ecological protocol has been described for the oxidation of methyl arenes and their analogs to the corresponding carbonyl compounds and epoxidation reactions of alkenes with molecular oxygen (O2) or air as a green oxygen source, under mild reaction conditions. The nano Ni/g-C3N4 exhibited high photocatalytic activity, stability, and selectivity in the C?H activation of methyl arenes, methylene arenes, and epoxidation of various alkenes under visible- light irradiation without the use of an oxidizing agent and under base free conditions.
• Akrami, Zahra,Hosseini-Sarvari, Mona
• supporting information

  (2020/10/13)
•