cas 97-99-4, Tetrahydrofurfuryl alcohol | Articles data

Articles about 97-99-4Total 256 be found

Article title
Article abstract
Author
Journal number and time
Download

Supported Ultrafine NiCo Bimetallic Alloy Nanoparticles Derived from Bimetal-Organic Frameworks: A Highly Active Catalyst for Furfuryl Alcohol Hydrogenation
Highly dispersed NiCo bimetallic alloy nanoparticles have been successfully immobilized on the SiO2 frameworks by using heteronuclear metal-organic frameworks (MOFs) as metal alloy precursors. Catalyst characterizations revealed that the average size of NiCo alloy particles was less than 1 nm, with a total metal loading of about 20 wt %. As compared to individual Ni or Co MOF-derived catalysts and the catalysts prepared by the conventional impregnation method, the ultrafine NiCo/SiO2-MOF catalyst showed a much better catalytic performance in the catalytic hydrogenation of furfuryl alcohol (FA) to tetrahydrofurfuryl alcohol (THFA) under mild conditions, giving 99.8% conversion of FA and 99.1% selectivity to THFA. It was found that a significant synergistic effect existed between Co and Ni within the subnanometer NiCo/SiO2-MOF catalyst, which was 2 and 20 times more active than Ni/SiO2-MOF and Co/SiO2-MOF, respectively.
Wang, Huanjun,Li, Xiaodan,Lan, Xiaocheng,Wang, Tiefeng
p. 2121 - 2128
(2018)
Read Online

Primary Anion-π Catalysis and Autocatalysis
Epoxide-opening ether cyclizations are shown to occur on π-acidic aromatic surfaces without the need of additional activating groups and with autocatalytic amplification. Increasing activity with the intrinsic π acidity of benzenes, naphthalenediimides (NDIs) and perylenediimides (PDIs) support that anion-π interactions account for function. Rate enhancements maximize at 270 for anion-π catalysis on fullerenes and at 5100 M-1 for autocatalysis. The occurrence of anion-π autocatalysis is confirmed with increasing initial rates in the presence of additional product. Computational studies on autocatalysis reveal transition state and product forming a hydrogen-bonded noncovalent macrocycle, like holding their hands and dancing on the active π surface, with epoxide opening and nucleophile being activated by anion-π interactions and hydrogen bonds to the product, respectively.
Zhang, Xiang,Hao, Xiaoyu,Liu, Le,Pham, Anh-Tuan,López-Andarias, Javier,Frontera, Antonio,Sakai, Naomi,Matile, Stefan
p. 17867 - 17871
(2018)
Read Online

A facile conversion of furfural to novel tetrahydrofurfuryl hemiacetals
An entirely new and highly selective method for preparation of novel tetrahydrofurfuryl hemiacetals is described. The process is based on the catalytic hydrogenation of furfural in an alcohol under mild reaction conditions and at very short reaction times. As a highly active and selective catalyst palladium supported on calcium carbonate is used. Basic sites of the catalyst support enhance the formation of furfuryl hemiacetal as the intermediate which is instantaneously hydrogenated into stable tetrahydrofurfuryl hemiacetal. About 85–90 % yields of tetrahydrofurfuryl hemialkylacetals can be achieved within 20 min by reaction of furfural in alcoholic solutions at 60 °C and 0.3 MPa of hydrogen. The mechanism of reductive acetalization of furfural into tetrahydrofurfuryl hemialkylacetals is proposed.
Dobro?ka, Edmund,Fulajtárová, Katarína,Horváth, Bla?ej,Hronec, Milan,Liptaj, Tibor
(2020)
Read Online

Highly selective low-temperature hydrogenation of furfuryl alcohol to tetrahydrofurfuryl alcohol catalysed by hectorite-supported ruthenium nanoparticles
Metallic ruthenium nanoparticles intercalated in hectorite (particle size ～ 4 nm) were found to catalyse the hydrogenation of furfuryl acohol to give tetrahydrofurfuryl alcohol in methanolic solution under mild conditions. The best results were obtained at 40 °C under a hydrogen pressure of 20 bar (conversion 100%, selectivity > 99%). After a total turnover number of 1423, the hectorite supported ruthenium nanoparticles are deactivated but can be recycled and regenerated.
Khan, Farooq-Ahmad,Vallat, Armelle,Suess-Fink, Georg
p. 1428 - 1431
(2011)
Read Online

Metal-organic-framework derived Co-Pd bond is preferred over Fe-Pd for reductive upgrading of furfural to tetrahydrofurfuryl alcohol
Combined noble-transition metal catalysts have been used to produce a wide range of important non-petroleum-based chemicals from biomass-derived furfural (as a platform molecule) and have garnered colossal research interest due to the urgent demand for sustainable and clean fuels. Herein, we report the palladium-modified metal-organic-framework (MOF) assisted preparation of PdCo3O4 and PdFe3O4 nanoparticles encapsulated in a graphitic N-doped carbon (NC) matrix via facile in situ thermolysis. This provides a change in selectivity with superior catalytic activity for the reductive upgrading of biomass-derived furfural (FA). Under the optimized reaction conditions, the newly designed PdCo3O4@NC catalyst exhibited highly efficient catalytic performance in the hydrogenation of furfural, providing 100% furfural conversion with 95% yield of tetrahydrofurfuryl alcohol (THFAL). In contrast, the as-synthesized Pd-Fe3O4@NC afforded a THFAL yield of 70% after an 8 h reaction with four consecutive recycling tests. Based on different characterization data (XPS, H2-TPR) for nanohybrids, we can conclude that the presence of PdCo-Nx active sites, and the multiple synergistic effects between Co3O4 and Pd(ii), Co3O4 and Pd0, as well as the presence of N in the carbonaceous matrix, are responsible for the superior catalytic activity and improved catalyst stability. Our strategy provides a facile design and synthesis process for a noble-transition metal alloy as a superior biomass refining, robust catalyst via noble metal modified MOFs as precursors.
Pendem, Saikiran,Bolla, Srinivasa Rao,Morgan, David J.,Shinde, Digambar B.,Lai, Zhiping,Nakka, Lingaiah,Mondal, John
p. 8791 - 8802
(2019)
Read Online

Highly selective hydrogenation of furfural and levulinic acid over Ni0.09Zn/NC600 derived from ZIFW-8
Highly selective hydrogenation of furfural and levulinic acid (LA) was studied over Ni0.09Zn/NC600 derived from zeolitic imidazolate frameworks. The existence of active Ni3ZnC0.7 particles in Ni0.09Zn/NC600 was confirmed by multiple characterizations. As a result, over Ni0.09Zn/NC600, 99.7% of furfural conversion (FC) and 100% of furan-2-ylmethanol selectivity (FMS) were achieved in isopropanol (IP) at 170 °C for 2 h, while FC and (tetrahydrofuran-2-yl)methanol (THFM) selectivity are 97.5% and 86.4% in water at 150 °C for 1 h. Over the same catalyst, LA was completely converted to γ-valerolactone in water at 95 °C for 0.5 h. The catalyst is still highly active after 6 cycles of recycling with 92.8% of FC and 100% of FMS in IP at 170 °C for 1.5 h and 90.1% of LA conversion and 100% of γ-valerolactone selectivity in water at 80 °C for 0.5 h.
Li, Zhi-Xin,Wei, Xian-Yong,Liu, Guang-Hui,Meng, Xing-Long,Yang, Zheng,Niu, Shuo,Zhang, Di,Gao, Hua-Shuai,Ma, Zhi-Hao,Zong, Zhi-Min
(2020)
Read Online

A novel Ru-polyethersulfone (PES) catalytic membrane for highly efficient and selective hydrogenation of furfural to furfuryl alcohol
A novel catalytic membrane has been synthesised, characterised and evaluated for the selective hydrogenation of furfural to furfuryl alcohol. Unlike conventional methods, involving high pressure and high H2:feed ratios, this work proposes an innovative ruthenium based Catalytic Membrane Reactor (CMR) to overcome mass transfer limitations, resulting in low H2 requirements, high catalytic activity and high selectivity towards furfuryl alcohol. A UV-curable hydrophilic anionic monomer acrylic acid was used as a coating material on a commercial PES membrane and subsequently Ru nanoparticles were added. The hydrogenation of furfural was carried out in a customised catalytic membrane reactor under mild conditions: 70 °C and 7 bar, exhibiting high catalytic activity towards furfuryl alcohol (selectivity >99%) with turnover frequency (TOF) as high as 48000 h-1, 2 orders of magnitude higher than those obtained so far.
Bagnato,Figoli,Ursino,Galiano,Sanna
p. 4955 - 4965
(2018)
Read Online

High-Temperature Synthesis of Carbon-Supported Bimetallic Nanocluster Catalysts by Enlarging the Interparticle Distance
Supported bimetallic nanoparticle catalysts with small size have attracted wide research attention in catalysis but are difficult to synthesize because high-temperature annealing required for alloying inevitably accelerates metal sintering and leads to larger particles. Here, we report a simple and scalable critical interparticle distance method for the synthesis of a family of bimetallic nanocluster catalysts with an average particle size of only 1.5 nm by using large-surface-area carbon black supports at high temperatures, which consist of 12 diverse combinations of 3 noble metals (Pt, Ru, and Rh) and 4 other metals (Cr, Fe, Zr, and Sn). In this strategy, high-temperature treatments ensure the formation of alloyed bimetallic nanoparticles and enlargement of the interparticle distance on high-surface-area supports significantly suppresses metal sintering. The prepared ultrafine Pt2Sn and RuSn nanocluster catalysts exhibited enhanced performance in catalyzing the synthesis of aromatic secondary amines and the selective hydrogenation of furfural, respectively.
Zuo, Lu-Jie,Xu, Shi-Long,Wang, Ao,Yin, Peng,Zhao, Shuai,Liang, Hai-Wei
supporting information
p. 2719 - 2723
(2022/02/16)

Organic modifiers promote furfuryl alcohol ring hydrogenation via surface hydrogen-bonding interactions
Interactions between surface adsorbed species can affect catalyst reactivity, and thus, the ability to tune these interactions is of considerable importance. Deposition of organic modifiers provides one method of intentionally introducing controllable surface interactions onto catalyst surfaces. In this study, Pd/Al2O3 catalysts were modified with either thiol or phosphonic acid (PA) ligands and tested in the hydrogenation of furanic species. The thiol modifiers were found to inhibit ring hydrogenation (RH) activity, with the degree of inhibition trending with the thiol surface coverage. This suggests that thiols do not strongly interact with the reactants and simply serve to block active sites on the Pd surface. PAs, on the other hand, were found to enhance RH when furfuryl alcohol (FA) was used as the reactant. Density functional theory calculations suggested that this enhancement was due to hydrogen-bonding interactions between FA-derived surface intermediates and PA modifiers. Here, installation of hydrogen-bonding groups on the Pd surface served to preferentially stabilize RH product states. Furthermore, the promotional effect on the RH of FA was observed to be greater when a higher-coverage PA was used, providing a rate more than twice that of the unmodified Pd/Al2O3. The results of this work suggest that organic ligands can be designed to impart tunable surface interactions on heterogeneous catalysts, providing an additional method of controlling catalytic performance.
Coan, Patrick D.,Farberow, Carrie A.,Griffin, Michael B.,Medlin, J. Will
p. 3730 - 3739
(2021/04/07)

Hydrogenolysis of Furfuryl Alcohol to 1,2-Pentanediol Over Supported Ruthenium Catalysts
Hydrogenolysis of the furan rings of furfural and furfuryl alcohol, which can be obtained from biomass, has attracted attention as a method for obtaining valuable chemicals such as 1,2-pentanediol. In this study, we examined the hydrogenolysis of furfuryl alcohol to 1,2-pentanediol over Pd/C, Pt/C, Rh/C, and various supported Ru catalysts in several solvents. In particular, we investigated the effects of combinations of solvents and supports on the reaction outcome. Of all the tested combinations, Ru/MgO in water gave the best selectivity for 1,2-pentanediol: with this catalyst, 42 % selectivity for 1,2-pentanediol was achieved upon hydrogenolysis of furfuryl alcohol for 1 h at 463 K. In contrast, reaction in water in the presence of Ru/Al2O3 afforded cyclopentanone and cyclopentanol by means of hydrogenation and rearrangement reactions.
Yamaguchi, Aritomo,Murakami, Yuka,Imura, Tomohiro,Wakita, Kazuaki
p. 731 - 736
(2021/06/12)

In-Situ Formation of Ni-C-Al2O3 Catalyst from MOFs@Al2O3 Composite for Furfuryl Alcohol Hydrogenation to Tetrahydrofurfuryl Alcohol
Hydrogenation of biomass-derived furfuryl alcohol to widely used tetrahydrofurfuryl alcohol is an important industrial route, which however calls for a more efficient catalyst. In this work, a highly selective and stable Ni-C-Al2O3 catalyst for furfuryl alcohol hydrogenation to tetrahydrofurfuryl alcohol is reported. The catalyst precursor is prepared by in-situ growth of Ni-based metal organic frameworks (Ni-BTC) on Al2O3 and then the precursor undergoes thermal decomposition to obtain the catalyst directly. For comparison, Ni-C/Al2O3 acquired from pyrolysis of physically mixed Ni-MOFs with Al2O3 and Ni/Al2O3 prepared by impregnation method are also tested as the hydrogenation catalysts. The prepared catalysts are characterized by a series of techniques, including XRD, FT-IR, TG, TEM, SEM, XPS and BET to reveal the relationship between the catalysts structure and their performance. The results show that small metal Ni particle size and appropriate interaction between Ni and the support, which benefit from the in-situ preparation method are key factors that ensure the high furfuryl alcohol conversion (99.8%) and high selectivity to tetrahydrofurfuryl alcohol (98.2%) at moderate reaction conditions (120?°C, 30?min, 4?MPa H2). Graphical Abstract: [Figure not available: see fulltext.].
Guo, Qirui,Liu, Shanshan,Wang, Yuan,Zhang, Yidong
(2021/11/22)

Unravelling the one-pot conversion of biomass-derived furfural and levulinic acid to 1,4-pentanediol catalysed by supported RANEY Ni-Sn alloy catalysts
Bimetallic Ni-Sn alloys have been recognised as promising catalysts for the transformation of furanic compounds and their derivatives into valuable chemicals. Herein, we report the utilisation of a supported bimetallic RANEY nickel-tin alloy supported on aluminium hydroxide (RNi-Sn(x)/AlOH; x is Ni/Sn molar ratio) catalysts for the one-pot conversion of biomass-derived furfural and levulinic acid to 1,4-pentanediol (1,4-PeD). The as prepared RNi-Sn(1.4)/AlOH catalyst exhibited the highest yield of 1,4-PeD (78%). The reduction of RNi-Sn(x)/AlOH with H2 at 673-873 K for 1.5 h resulted in the formation of Ni-Sn alloy phases (e.g., Ni3Sn and Ni3Sn2) and caused the transformation of aluminium hydroxide (AlOH) to amorphous alumina (AA). The RNi-Sn(1.4)/AA 673 K/H2 catalyst contained a Ni3Sn2 alloy as the major phase, which exhibited the best yield of 1,4-PeD from furfural (87%) at 433 K, H2 3.0 MPa for 12 h and from levulinic acid (up to 90%) at 503 K, H2 4.0 MPa, for 12 h. Supported RANEY Ni-Sn(1.5)/AC and three types of supported Ni-Sn(1.5) alloy (e.g., Ni-Sn(1.5)/AC, Ni-Sn(1.5)/c-AlOH, and Ni-Sn(1.5)/γ-Al2O3) catalysts afforded high yields of 1,4-PeD (65-87%) both from furfural and levulinic acid under the optimised reaction conditions.
Ansyah, Fathur Razi,Astuti, Maria Dewi,Hara, Takayoshi,Husain, Sadang,Mustikasari, Kamilia,Rodiansono,Shimazu, Shogo
p. 241 - 250
(2022/01/19)

MOF-derived hcp-Co nanoparticles encapsulated in ultrathin graphene for carboxylic acids hydrogenation to alcohols
Highly efficient conversion of carboxylic acids to valuable alcohols is a great challenge for easily corroded non-noble metal catalysts. Here, a series of few-layer graphene encapsulated metastable hexagonal closed-packed (hcp) Co nanoparticles were fabricated by reductive pyrolysis of metal-organic framework precursor. The sample pyrolyzed at 400 °C (hcp-Co@G400) presented outstanding performance and stability for converting a variety of functional carboxylic acids and its turnover frequency was one magnitude higher than that of conventional facc-centered cubic (fcc) Co catalysts. In situ DRIFTS spectroscopy of model reaction acetic acid hydrogenation and DFT calculation results confirm that carboxylic acid initially undergoes dehydroxylation to RCH2CO* followed by consecutive hydrogenation to RCH2CH2OH through RCH2COH*. Acetic acid prefers to vertically adsorb at hcp-Co (0 0 2) facet with a much lower adsorption energy than parallel adsorption at fcc-Co (1 1 1) surface, which plays a key role in decreasing the activation barrier of the rate-determining step of acetic acid dehydroxylation.
Dong, Mei,Fan, Weibin,Gao, Xiaoqing,Zhu, Shanhui
p. 201 - 211
(2021/06/03)

Interfacial effect of Pd supported on mesoporous oxide for catalytic furfural hydrogenation
Highly dispersed Pd is loaded onto different types of mesoporous oxide supports to investigate the synergetic metal-support effect in catalytic furfural (FAL) hydrogenation. Ordered mesoporous Co3O4, MnO2, NiO, CeO2, and Fe2O3 are prepared by the nanocasting and the supported Pd on mesoporous oxide catalysts are obtained by the chemical reduction method. It is revealed that mesoporous oxides play an important role on Pd dispersion as well as the redox behavior of Pd, which determines the final FAL conversion. Among the catalysts used, Pd/Co3O4 shows the highest conversion in FAL hydrogenation and distinct product selectivity toward 2-methylfuran (MF). While FAL is converted via two distinct pathways to produce either furfuryl alcohol (FA) via aldehyde hydrogenation or MF via hydrogenolysis, MF as a secondary product is derived from FA via the hydrogenolysis of C–O over the Pd/Co3O4 catalyst. It is revealed that FAL is hydrogenated to FA preferentially on the Pd surface; then the secondary hydrogenolysis to MF from FA is further promoted at the interface between Pd and Co3O4. We confirm that the reaction pathway over Pd/Co3O4 is totally different from other catalysts such as Pd/MnO2, which produces FA dominantly. The characteristics of the mesoporous oxides influence the Pd-oxide interfaces, which determine the activity and selectivity in FAL hydrogenation.
Lee, Hojeong,Nguyen-Huy, Chinh,Jeong Jang, Eun,Lee, Jihyeon,Yang, Euiseob,Lee, Man Sig,Kwak, Ja Hun,An, Kwangjin
p. 291 - 300
(2020/03/05)

Ru Nanoparticles on a Sulfonated Carbon Layer Coated SBA-15 for Catalytic Hydrogenation of Furfural into 1, 4-pentanediol
Furfural (FFR) is one of the most important biomass-derived chemicals. Its large-scale availability calls for the exploration of new transformation methods for further valorization. Herein, we demonstrate that Ru nanoparticles (Ru NPs)-supported on a sulfonated carbon layer coated SBA-15 can be employed as an efficient bi-functional catalyst for one step conversion of FFR into 1,4-pentanediol (1,4-PeDO). The optimum bi-functional catalyst can afford the full the conversion of FFR and 86% selectivity to 1,4-PeDO. The catalysts have been characterized thoroughly by using a complementary combination of powder X-ray diffraction, N2 adsorption–desorption, scanning/transmission electron microscopy, Fourier transform infrared spectroscopy, elemental analysis, and X-ray photoelectron spectroscopy. The characterization revealed that acidic groups (–SO3H) have been introduced on the surface of the carbon layer coated SBA-15 support after sulfonation with 98% H2SO4 and the surface acidity can be tuned facilely by the sulfonating time. Meantime, Ru(0) sites was highly dispersed via an impregnation and sequential reduction and directly adjacent to the surface –SO3H group. There existed an electronic interaction between Ru(0) sites and sulfonic groups, in which the electronic transfer from sulfonic sites to Ru(0) sites occurred. Br?nsted acid sites (–SO3H) have a significant influence on the FFR conversion and the selectivity to 1,4-PeDO. The ordered mesoporous structure, the appropriate density of acid sites and the electron-rich Ru(0) sites accounted for the the excellent performance of the catalyst for an efficient production of 1,4-PeDO from FFR. Graphic Abstract: [Figure not available: see fulltext.].
Cui, Kai,Qian, Wei,Shao, Zhengjiang,Zhao, Xiuge,Gong, Honghui,Wei, Xinjia,Wang, Jiajia,Chen, Manyu,Cao, Xiaoming,Hou, Zhenshan
p. 2513 - 2526
(2021/02/05)

Catalytic hydrogenation of furfural to tetrahydrofurfuryl alcohol using competitive nickel catalysts supported on mesoporous clays
Nickel catalysts supported on mesoporous clays with different acid properties, such as montmorillonite MK-10, Al-pillared montmorillonite, mesoporous Na-saponite and mesoporous H-saponite, were prepared, characterized and tested for the hydrogenation of furfural to tetrahydrofurfuryl alcohol (THFA). Clays were also modified introducing basicity through magnesium oxide in different amounts. Catalysts with higher acidity or low amounts of metallic centres favoured deactivation and/or selectivity to the non-desired products. Interestingly, the addition of MgO both neutralized the acidity of the montmorillonite supports and improved the hydrogenation of the furanic ring, resulting in higher selectivity to THFA. The best catalyst was the one prepared with montmorillonite MK-10 covered by 30 wt% of magnesium oxide and with 8.8 % of the Ni metal phase achieving total conversion and total selectivity to THFA. The activity of this catalyst was maintained after several reuses.
Sunyol,English Owen,González,Salagre,Cesteros
(2020/11/12)

Selective hydrogenation of furfural to furfuryl alcohol over Pd/TiH2 catalyst
In this work, the selective hydrogenation of furfural to furfuryl alcohol has been studied over Pd/TiH2 catalysts. The catalytic performances of several catalysts with different Pd loading (0.2–3% in weight) were discussed, among which a higher selectivity to furfuryl alcohol was obtained over 0.5Pd/TiH2 and it gave rise to a 73% furfural alcohol selectivity at complete conversion at 60 °C. The physicochemical properties of catalysts were well characterized by TEM, XRD, XPS, Raman, TPR and TPD, as well as in-situ DRIFT for the adsorption of the reactant. The size and the electronic state of Pd particles, and the surface defects of catalysts presented significant influence on the catalytic performance. The furfural is preferentially adsorbed with its C=O bond on the boundary of Pd particle and TiH2 support, leading to the high selectivity to furfuryl alcohol.
Wang, Zhuangqing,Wang, Xinchao,Zhang, Chao,Arai, Masahiko,Zhou, Leilei,Zhao, Fengyu
(2021/05/13)

A Cationic Ru(II) Complex Intercalated into Zirconium Phosphate Layers Catalyzes Selective Hydrogenation via Heterolytic Hydrogen Activation
Catalytic hydrogenations constitute economic and clean transformations to produce pharmaceutical and a multitude of fine chemicals in chemical industry. Herein, we report a cationic Ru(II) complex intercalated into zirconium phosphate (ZrP) layers that enables the efficient catalytic conversion of furfural and other biomass-derived carbonyl compounds into the corresponding alcohols through selective hydrogenation of C=O group. The ZrP layers acted not only as a support for the Ru-complex, but also as the new ligands to tune the Ru(II) center via forming Ru?O bond. The resulting catalysts exhibit excellent catalytic performance and can be easily recycled for six times without significant loss of activity and selectivity. The Ru(II) complex-intercalated catalysts have been characterized by XRD, SEM, HRTEM, HAADF-STEM, XPS, FT-IR, DR-UV/Vis, EXAFS and XANES. Especially, it is observed that the appropriate interlayer spacing between ZrP layers is favorable to stabilize the Ru(II) complex. Notably, on the basis of the further characterization and density functional theory (DFT) calculation, it is identified that the interaction of cationic Ru(II) complex and P?OH group within ZrP layers leads to the high catalytic performance in selective hydrogenation, and the newly formed Ru?O?P species plays a crucial role in the heterolytic hydrogen activation and selective hydrogenation of biomass-derived compounds containing a carbonyl group.
Chen, Manyu,Xia, Jie,Li, Huan,Zhao, Xiuge,Peng, Qingpo,Wang, Jiajia,Gong, Honghui,Dai, Sheng,An, Pengfei,Wang, Haifeng,Hou, Zhenshan
p. 3801 - 3814
(2021/08/03)

Bimetallic RuNi nanoparticles as catalysts for upgrading biomass: Metal dilution and solvent effects on selectivity shifts
RuNi nanoparticles (NP) were prepared by decomposition of [Ru(η4-C8H12)(η6-C8H10)] and [Ni(η4-C8H12)2] by H2 in the presence of polyvinylpyrrolidone (PVP) at 85 °C using several Ru/Ni ratios. The nanoparticles display a segregated structure in which Ni is on the surface, as ascertained by wide angle X-ray scattering (WAXS). The catalytic activity in the selective hydrogenation of furfural of these RuNi NP was correlated with the Ru content. High selectivity towards the partially hydrogenated product 2-(hydroxymethyl)furan (HF) was found when carrying out the reaction in tetrahydrofuran (THF). A different scenario was found when using a protic polar solvent, 1-propanol. Catalysts displaying Ru on the surface were able to hydrogenate the heteroaromatic ring, while those with Ni on the surface were highly selective towards the partially hydrogenated product. In addition, Ru surfaces were prone to catalyse the acetalization reaction in the presence of the alcoholic solvent, while the addition of Ni supressed this reactivity. Density functional theory (DFT) calculations performed on hydrogenated Ru nanoparticles (Ru55H70) show differences in the adsorption energies of several reagents, products, reaction intermediates, and solvents onto the Ru NP surface, which are in line with the experimental catalytic results. This journal is
Axet, M. Rosa,Cardona-Farreny, Miquel,Del Rosal, Iker,Dinoi, Chiara,Esvan, Jerome,Lecante, Pierre,Philippot, Karine,Poteau, Romuald
supporting information
p. 8480 - 8500
(2021/11/17)

Heterogeneous Hydrogenation of Quinoline Derivatives Effected by a Granular Cobalt Catalyst
We communicate a convenient method for the pressure hydrogenation of quinolines in aqueous solution by using a particulate cobalt-based catalyst that is prepared in situ from simple Co(OAc)2 4H2O through reduction with abundant zinc powder. This catalytic protocol permits a brisk and atom-efficient access to a variety of 1,2,3,4-tetrahydroquinolines thereby relying solely on easy-to-handle reagents that are all readily obtained from commercial sources. Both the reaction setup assembly and the autoclave charging procedure are conducted on the bench outside an inert-gas-operated containment system, thus rendering the overall synthesis time-saving and operationally very simple.
Timelthaler, Daniel,Topf, Christoph
(2021/11/22)

Aqueous phase hydrogenation of furfural to tetrahydrofurfuryl alcohol over Pd/UiO-66
A Pd/UiO-66 catalyst was synthesized with well-dispersed Pd nanoparticles. The obtained catalyst was tested in the hydrogenation of furfural to tetrahydrofurfuryl alcohol in various solvents, Water was found to be the most suitable solvent. Pd/UiO-66 exhibited much higher activity than Pd/SiO2 and Pd/γ-Al2O3, completely converting furfural to tetrahydrofurfuryl alcohol with 100% selectivity under mild conditions. The hydrogenation of C[dbnd]O moiety in tetrahydrofurfural was rate-determining step. Static adsorption measurement indicated that the adsorption of furfural on UiO-66 was significantly stronger than that on SiO2 or γ-Al2O3, suggesting that the adsorption play an important role in the gas-liquid-solid furfural hydrogenation reaction.
Kogan, Victor M.,Liu, Ying-Ya,Sun, Zhichao,Wang, Anjie,Wang, Chunhua,Wang, Yao,Yu, Zhiquan
(2020/10/09)

Highly Controllable Hydrogenative Ring Rearrangement and Complete Hydrogenation Of Biobased Furfurals over Pd/La2B2O7 (B=Ti, Zr, Ce)
Developing a highly selective catalyst to upgrade furfurals (5-hydroxymethyl furfural and furfural) to cyclopentanones (3-hydroxymethyl cyclopentanone and cyclopentanone) and tetrahydrofuran alcohols (2,5-bishydroxymethyl tetrahydrofuran and tetrahydrofuran alcohol) is highly significant for biobased fine chemical synthesis. Here, a series of La2B2O7 (B=Ti, Zr, Ce) metal oxides, featuring the same chemical formula but different topological structures are fabricated. After Pd loading, the Lewis acidity and metal-support interaction are well governed by the support type, which further affects the hydrogenation and acid-catalyzed ability. A greater than 82 % yield of cyclopentanones is obtained via a hydrogenative ring rearrangement route over Pd/La2Ti2O7. However, Pd/La2Ce2O7 shows high catalytic efficiency for tetrahydrofuran alcohols with an approximately 80 % yield via a complete hydrogenation route. Additionally, the catalyst exhibits outstanding recycling performance and structural stability. This study presents an interesting design strategy for the selective preparation of cyclopentanones and tetrahydrofuran alcohols through the regulation of the adsorption mechanism.
Tong, Zhikun,Gao, Rui,Li, Xiang,Guo, Lingyun,Wang, Jun,Zeng, Zheling,Deng, Qiang,Deng, Shuguang
p. 4549 - 4556
(2021/09/09)

The discovery of a potent and selective pyrazolo-[2,3-e]-[1,2,4]-triazine cannabinoid type 2 receptor agonist
The development of selective CB2 receptor agonists is a promising therapeutic approach for the treatment of inflammatory diseases, without CB1 receptor mediated psychoactive side effects. Preliminary structure-activity relationship studies on pyrazoylidene benzamide agonists revealed the -ylidene benzamide moiety was crucial for functional activity at the CB2 receptor. A small library of compounds with varying linkage moieties between the pyrazole and substituted phenyl group has culminated in the discovery of a potent and selective pyrazolo-[2,3-e]-[1,2,4]-triazine agonist 19 (CB2R EC50 = 19 nM, CB1R EC50 > 10 μM). Docking studies have revealed key structural features of the linkage group that are important for potent functional activity.
Moir, Michael,Lane, Samuel,Montgomery, Andrew P.,Hibbs, David,Connor, Mark,Kassiou, Michael
(2020/12/21)

Furfural hydrodeoxygenation (HDO) over silica-supported metal phosphides – The influence of metal–phosphorus stoichiometry on catalytic properties
The gas-phase hydrodeoxygenation (HDO) of furfural, a model compound for bio-based conversion, was investigated over transition metal phosphide catalysts. The HDO activity decreases in the order Ni2P ≈ MoP > Co2P ≈ WP ? Cu3P > Fe2P. Nickel phosphide phases (e.g., Ni2P, Ni12P5, Ni3P) are the most promising catalysts in the furfural HDO. Their selectivity to the gasoline additives 2-methylfuran and tetrahydro-2-methylfuran can be adjusted by varying the P/Ni ratio. The effect of P on catalyst properties as well as on the reaction mechanism of furfural HDO were investigated in depth for the first time. An increase of the P stoichiometry weakens the furan-ring/catalyst interaction, which contributes to a lower ring-opening and ring-hydrogenation activity. On the other hand, an increasing P content does lead to a stronger carbonyl/catalyst interaction, i.e., to a stronger η2(C, O) adsorption configuration, which weakens the C1[sbnd]O1 bond (Scheme 1) in the carbonyl group and enhances the carbonyl conversion. Phosphorus species can also act as Br?nsted acid sites promoting C1[sbnd]O1 (Scheme 1) hydrogenolysis of furfuryl alcohol, hence contributing to higher production of 2-methylfuran.
Lan, Xuefang,Pestman, Robert,Hensen, Emiel J.M.,Weber, Thomas
p. 181 - 193
(2021/02/27)

Effect of Ni Metal Content on Emulsifying Properties of Ni/CNTox Catalysts for Catalytic Conversion of Furfural in Pickering Emulsions
Ni/CNTox catalysts with variable metal content have been prepared to investigate their emulsifying and catalytic properties for the liquid-phase conversion of furfural. The solid catalysts and emulsions were analyzed by several characterization techniques. The catalytic activity linearly increased with increasing Ni content (up to 10 wt.%) before dropping down again for a Ni content of 15 wt.%. The loss of catalytic activity was attributed to larger emulsion droplets formed by the inhibition of hydrophilic sites. All Ni/CNTox catalysts were highly selective to cyclopentanone as a main product, while several changes regarding secondary products were observed. Ni/CNTox catalysts with a Ni content up to 10 wt.% favor the formation of levulinic acid, while catalysts with a Ni content of 15 wt.% were selective to tetrahydrofurfuryl alcohol. This was attributed to an inhibition of the acid sites thus favoring the catalyst's hydrogenation capacity.
Herrera,Pinto-Neira,Fuentealba,Sepúlveda,Rosenkranz,García-Fierro,González,Escalona
p. 682 - 694
(2020/12/01)

Hydrogenative ring-rearrangement of furfural to cyclopentanone over pd/uio-66-no2 with tunable missing-linker defects
Upgrading furfural (FAL) to cyclopentanone (CPO) is of great importance for the synthesis of high-value chemicals and biomass utilization. The hydrogenative ring-rearrangement of FAL is catalyzed by metal-acid bifunctional catalysts. The Lewis acidity is a key factor in promoting the rearrangement of furan rings and achieving a high selectivity to CPO. In this work, highly dispersed Pd nanoparticles were successfully encapsulated into the cavities of a Zr based MOF, UiO-66-NO2, by impregnation using a double-solvent method (DSM) followed by H2 reduction. The obtained Pd/UiO-66-NO2 catalyst showed a significantly better catalytic performance in the aforementioned reaction than the Pd/UiO-66 catalyst due to the higher Lewis acidity of the support. Moreover, by using a thermal treatment. The Lewis acidity can be further increased through the creating of missing-linker defects. The resulting defective Pd/UiO-66-NO2 exhibited the highest CPO selectivity and FAL conversion of 96.6% and 98.9%, respectively. In addition, the catalyst was able to maintain a high activity and stability after four consecutive runs. The current study not only provides an efficient catalytic reaction system for the hydrogenative ring-rearrangement of furfural to cyclopentanone but also emphasizes the importance of defect sites.
Leus, Karen,Liu, Ying-Ya,Shi, Chuan,Sun, Zhichao,Van Der Voort, Pascal,Wang, Anjie,Wang, Chunhua,Wang, Yao,Yang, Yuhao,Yu, Zhiquan
(2021/09/28)

Selective tandem hydrogenation and rearrangement of furfural to cyclopentanone over CuNi bimetallic catalyst in water
Tandem catalysis for the hydrogenation rearrangement of furfural (FA) provides an attractive solution for manufacturing cyclopentanone (CPO) from renewable biomass resources. The CuNi/Al-MCM-41 catalyst was synthesized and afforded excellent catalytic performance with 99.0% conversion and 97.7% selectivity to CPO in a near-neutral solution under 2.0 MPa H2 at 160 °C for 5 h, much higher than those on other molecular sieve supports including MCM-41, SBA-15, HY, and ZSM-5. A small amount of Al highly dispersed in MCM-41 plays an anchoring role and ensures the formation of highly dispersed CuNi bimetallic nanoparticles (NPs). The remarkably improved catalytic performance may be attributed to the bimetallic synergistic and charge transfer effects. In addition, the initial FA concentration and the aqueous system pH required precise control to minimize polymerization and achieve high selectivity of CPO. Fourier transform infrared spectroscopy and mass spectra results indicated that polymerization was sensitive to pH values. Under acidic conditions, FA and intermediate furfuryl alcohol polymerize, while the intermediate 4-hydroxy-2-cyclopentenone mainly polymerizes under alkaline conditions, blocking the cascade of multiple reactions. Therefore, near-neutral conditions are most suitable for minimizing the impact of polymerization. This study provides a useful solution for the current universal problems of polymerization side reactions and low carbon balance for biomass conversion.
Gao, Jin,Liu, Xin,Luo, Yang,Ma, Hong,Sun, Yuxia,Xu, Jie,Zhang, Meiyun,Zhang, Shujing
p. 2216 - 2224
(2021/09/20)

Selective aqueous-phase hydrogenation of furfural to cyclopentanol over Ni-based catalysts prepared from Ni-MOF composite
Metal-organic frameworks (MOFs) as an emerging class of porous materials exhibit some unique advantages, including controllable composition, a large surface area, high porosity, and so on. In this work, the spherical NiMo bimetal catalysts supported on porous carbon matrix were prepared using a simple wet impregnation method and studied for selective hydrogenation of furfural (FFA). Three different catalysts were investigated including Ni/C-Mo-BTC, Ni/C-Mo-DHTA and Ni/C-Mo-PTA. Of the catalysts studied the Ni/C-Mo-BTC catalyst could achieve the highest selectivity of CPL (up to 90%) under moderate reaction conditions (140 °C, 2 MPa, 2 h) in aqueous medium. In addition, other Ni-based catalysts (Ni/C-Fe, Ni/C-Zn, Ni/C-Cu, Ni/C-Ce) were also investigated to achieve yields of 20–70% under the same reaction conditions. The influence of temperature, H2 pressure, time and solvent were investigated for the best performing catalyst. Based on the optimal reaction condition, various of furfural derivatives could also be effectively transferred to produce corresponding products. The detailed physicochemical characterization was carried out by means of XRD, SEM, TEM, XPS, NH3-TPD and Raman analysis. In the end, the optimal Ni/C-Mo0.4 catalyst could be recycled magnetically and efficiently applied in the next run for five consecutive recycling tests in the FFA hydrogenation to CPL. The results suggested Ni/C-Mo0.4 catalyst occurred to increasingly favor the formation of Ni-Mo alloys and suggested a metallic active site in FFA hydrogenation with the addition of element Mo. Mechanism study indicated that water was a key factor contributing to the formation of different desired products, which was responsible for the arrangement of furan compound.
Chen, Changzhou,Jiang, Jianchun,Li, Jing,Ren, Jurong,Wu, Dichao,Xia, Haihong,Zhou, Minghao
(2021/10/01)

Conversion of furfural to 2-methylfuran over CuNi catalysts supported on biobased carbon foams
In this study, carbon foams prepared from the by-products of the Finnish forest industry, such as tannic acid and pine bark extracts, were examined as supports for 5/5% Cu/Ni catalysts in the hydrotreatment of furfural to 2-methylfuran (MF). Experiments were conducted in a batch reactor at 503 K and 40 bar H2. Prior to metal impregnation, the carbon foam from tannic acid was activated with steam (S1), and the carbon foam from pine bark extracts was activated with ZnCl2 (S2) and washed with acids (HNO3 or H2SO4). For comparison, a spruce-based activated carbon (AC) catalyst and two commercial AC catalysts as references were investigated. Compressive strength of the foam S2 was 30 times greater than that of S1. The highest MF selectivity of the foam-supported catalysts was 48 % (S2, washed with HNO3) at a conversion of 91 %. According to the results, carbon foams prepared from pine bark extracts can be applied as catalyst supports.
Varila, Toni,M?kel?, Eveliina,Kupila, Riikka,Romar, Henrik,Hu, Tao,Karinen, Reetta,Puurunen, Riikka L.,Lassi, Ulla
p. 16 - 27
(2020/12/28)

Development of bimetallic Ni-Cu/SiO2 catalysts for liquid phase selective hydrogenation of furfural to furfuryl alcohol
Bimetallic Ni-Cu/SiO2 catalysts with different Cu loading (2–5 wt%) were developed for liquid phase selective hydrogenation of furfural to furfuryl alcohol. Among these, bimetallic 2%Ni-X%Cu/SiO2 (X = 2, 5) catalysts exhibited better
Weerachawanasak, Patcharaporn,Krawmanee, Pacharaporn,Inkamhaeng, Weerachat,Cadete Santos Aires, Francisco J.,Sooknoi, Tawan,Panpranot, Joongjai
(2020/11/24)

Catalytic Transfer Hydrogenation of Furfural over CuNi@C Catalyst Prepared from Cu–Ni Metal-Organic Frameworks
Abstract: Cu/Ni-based metal-organic frameworks (CuNi@BTC) were prepared with benzene-1,3,5-tricarboxylate (H3BTC) as the organic ligand via the solvothermal method, and were then calcinated under N2 atmosphere to form C-coated CuNi catalysts (CuNi@C). TEM showed that carbon material on the surface of CuNi@C was a graphene-like structure. Then transfer hydrogenation of furfural catalyzed by CuNi@C was tested with alcohols as the hydrogen donor to optimize the Cu : Ni ratio, metal : organic ligand ratio, solvothermal synthesis, and calcination conditions. It was found that strong synergistic effect between Cu and Ni in the CuNi@C significantly enhanced the furfural transfer hydrogenation activity and raised the furfural selectivity. The reaction conditions of furfural transfer hydrogenation such as catalyst dosage, hydrogen donor, reaction temperature, and reaction time were studied. The catalytic mechanism for CTH of FF over CuNi@C catalyst was discussed.
Feng Li,Jiang, Shanshan,Wang, Yue,Huang, Jin,Li, Cuiqin
p. 68 - 79
(2021/03/01)

Direct Amination of Biomass-based Furfuryl Alcohol and 5-(Aminomethyl)-2-furanmethanol with NH3 over Hydrotalcite-derived Nickel Catalysts via the Hydrogen-borrowing Strategy
A series of hydrotalcite-derived nickel catalysts were synthesized and employed for the direct amination of biomass-based furfuryl alcohol with NH3 via the hydrogen borrowing strategy. The effects of the Ni/Al molar ratio and calcination temperature of the NiAl hydrotalcite-like precursors on the performance of the NixAl-CT catalyst were investigated. The systematic characterization showed that the synergistic catalysis of the metal and acid-base sites was of vital importance for the amination of alcohols. In particular, the Ni2Al-600 catalyst with high amount of Ni0 sites (1.26 mmol g?1) and suitable density of acid-base sites (0.71 mmol g?1 and 1.10 mmol g?1, respectively) exhibited the best dehydrogenation capability and therefore excellent catalytic activity. An 84.1 % yield of furfurylamine with complete conversion of furfuryl alcohol was obtained under the reaction conditions of 180 °C and 0.4 MPa NH3 in 36 h. The presence of Ni3N in the spent catalyst, confirmed by XRD, TEM and XPS characterizations, was demonstrated to be responsible for the deactivation of the NixAl-CT catalyst. In addition, the Ni2Al-600 catalyst exhibited satisfactory performance toward another important biomass-related transformation of 5-(aminomethyl)-2-furanmethanol to 2,5-bis(aminomethyl)furan, with a yield of 70.5 %.
Zhou, Kuo,Xie, Ruihong,Xiao, Meiting,Guo, Darun,Cai, Zhuodi,Kang, Shimin,Xu, Yongjun,Wei, Jinjia
p. 2074 - 2085
(2021/03/03)

Method for continuously preparing gamma-valerolactone from furfuryl alcohol by one-step method
The invention discloses a method for integrally and continuously producing gamma-valerolactone from furfuryl alcohol through hydration and hydrogenation, which comprises the steps of by using furfuryl alcohol as a reaction raw material, hydrating furfuryl alcohol into levulinic acid under the action of a solid acid catalyst and a metal catalyst, and then hydrogenating to obtain gamma-valerolactone. According to the method, side reactions such as furfuryl alcohol hydrogenation or polymerization are reduced or avoided through sectional assembly of the catalyst; and meanwhile, gamma-valerolactone is used as a reaction solvent to improve the actual utilization concentration of furfuryl alcohol. The method is mild in reaction condition, separation and purification of the product from the solvent and separation of the catalyst from the product are avoided, the technological process can be effectively shortened, and the operation cost is saved.
-
Paragraph 0063-0066; 0079

(2021/04/26)

Development of effective bidentate diphosphine ligands of ruthenium catalysts toward practical hydrogenation of carboxylic acids
Hydrogenation of carboxylic acids (CAs) to alcohols represents one of the most ideal reduction methods for utilizing abundant CAs as alternative carbon and energy sources. However, systematic studies on the effects of metal-to-ligand relationships on the catalytic activity of metal complex catalysts are scarce. We previously demonstrated a rational methodology for CA hydrogenation, in which CA-derived cationic metal carboxylate [(PP)M(OCOR)]+ (M = Ru and Re; P = one P coordination) served as the catalyst prototype for CA self-induced CA hydrogenation. Herein, we report systematic trial- and-error studies on how we could achieve higher catalytic activity by modifying the structure of bidentate diphosphine (PP) ligands of molecular Ru catalysts. Carbon chains connecting two P atoms as well as Ar groups substituted on the P atoms of PP ligands were intensively varied, and the induction of active Ru catalysts from precatalyst Ru(acac)3 was surveyed extensively. As a result, the activity and durability of the (PP)Ru catalyst substantially increased compared to those of other molecular Ru catalyst systems, including our original Ru catalysts. The results validate our approach for improving the catalyst performance, which would benefit further advancement of CA self-induced CA hydrogenation.
Saito, Susumu,Wen, Ke,Yoshioka, Shota
p. 1510 - 1524
(2021/06/18)

Self-regulated catalysis for the selective synthesis of primary amines from carbonyl compounds
Most current processes for the general synthesis of primary amines by reductive amination are performed with enormously excessive amounts of hazardous ammonia. It remains unclear how catalysts should be designed to regulate amination reaction dynamics at a low ammonia-to-substrate ratio for the quantitative synthesis of primary amines from the corresponding carbonyl compounds. Herein we show a facile control of the reaction selectivity in the layered boron nitride supported ruthenium catalyzed reductive amination reaction. Specifically, locating ruthenium to the edge surface of layered boron nitride leads to an increased hydrogenation activity owing to the enhanced interfacial electronic effects between ruthenium and the edge surface of boron nitride. This enables self-accelerated reductive amination reactions which quantitatively synthesize structurally diverse primary amines by reductive amination of carbonyl compounds with twofold ammonia. This journal is
Fan, Xiaomeng,Gao, Jin,Gao, Mingxia,Jia, Xiuquan,Ma, Jiping,Xu, Jie
supporting information
p. 7115 - 7121
(2021/09/28)

Anionic Amphiphilic Cyclodextrins Bearing Oleic Grafts for the Stabilization of Ruthenium Nanoparticles Efficient in Aqueous Catalytic Hydrogenation
Oleic succinyl β-cyclodextrin was proved to be efficient for the stabilization of ruthenium nanoparticles (NPs) in aqueous medium. These NPs were characterized by FTIR spectroscopy and transition electron microscopy (TEM). The catalytic activity of these NPs was evaluated in the aqueous hydrogenation of petrosourced and biosourced unsaturated compounds such as benzene and furfural derivatives. The catalytic system can be easily recycled and reused up to nine runs without any loss of activity and selectivity, demonstrating its robustness.
Cocq, Aurélien,Léger, Bastien,No?l, Sébastien,Bricout, Hervé,Djeda?ni-Pilard, Florence,Tilloy, Sébastien,Monflier, Eric
p. 1013 - 1018
(2019/12/27)

Silica/titania composite-supported NiCo catalysts with combined catalytic effects for phenol hydrogenation under fast and mild conditions
The effect of titanium as a promoter for the nickel-cobalt/silica-titania (NiCo/Si-Ti) catalyst in the hydrogenation of phenol was comparatively studied. In the phenol hydrogenation under mild reaction conditions (1 MPa H2 pressure and 100 °C), the Ti-promoter induces the formation of the Coδ??OV?Ti3+ active sites and enhances the hydrogenation activity of the NiCo/Si catalyst to convert phenol to cyclohexanol. The catalytic hydrogenation with the optimal composition of the NiCo/Si-1.0Ti (Si:Ti ratio of 8.5:1) catalyst was completed within 1 h (conversion 98.2 % and selectivity >99 %), which was more efficiently than that with other Ti-doped catalysts and NiCo/Si as baseline, indicating a strong positive synergistic effect between the metal (Ni-Co) and support (Ti-Si) components of the catalyst in this reaction. Additionally, the kinetics, pathway and catalytic mechanism of the hydrogenation of phenol are also examined. Furthermore, the NiCo/Si-1.0Ti catalysts also showed a good performance at reducing the unstable oxygenated compounds in the bio-oil.
Li, Yucheng,Liu, Jing,He, Jing,Wang, Luying,Lei, Jiandu
(2020/01/09)

Total hydrogenation of bio-derived furans over supported Ru subnanoclusters prepared via amino acid-assisted deposition
Development of a highly efficient and robust catalyst with reduced usage of noble metals is extremely desirable for selective hydrogenations of furan-containing bio-based feedstocks, which represents an attractive and sustainable alternative to petrochemical resources. Herein, we describe a new type of well-dispersed Ru subnanoclusters (ca. 0.50 wt%) supported on commercial P25 TiO2 material obtained from a facile and effective amino acid-assisted deposition-precipitation strategy. The as-synthesized catalyst exhibits superior catalytic activity and selectivity for direct hydrogenation of industrially important furfural as well as a range of structurally diverse bio-based furanic compounds to their corresponding fully hydrogenated derivatives. An average turnover frequency (ATOF) value as high as 367 h-1 at 80 °C and 4 MPa H2 is obtained, which is the highest reported value. This catalyst also shows stable furfural total hydrogenation in 5 reaction cycles conducted at 80 °C (52 mmol-scale, turnover number up to 12?500). In terms of the kinetic and structural characterizations, the key performances of the ultrasmall Ru clusters are proposed to mainly originate from an enhanced number of unsaturated surface Ru atoms and change in local coordination environment. Our work highlights the importance of the subnanometric size of Ru clusters in the advancement of efficient and affordable approaches towards bio-based chemical production.
Qian, Yang,Li, Ze-Jun,Du, Xian-Long,Zhang, Qi,Zhao, Yi,Liu, Yong-Mei,Cao, Yong
p. 850 - 859
(2020/02/25)

Catalytic production of 1,4-pentanediol from furfural in a fixed-bed system under mild conditions
Furfural is one of the most important biomass-derived chemicals. Its large-scale availability calls for the exploration of new transformation methods for further valorization. Here we report on the direct, one-step conversion of furfural into 1,4-pentanediols (1,4-PeDs) using a combination of Amberlyst-15 and Ru-FeOx/AC catalysts. It is interesting to find that the introduction of a suitable amount of FeOxresults in a great improvement in the dispersion of Ru and a decrease in the Lewis acidity. Both XPS and H2-TPR show that there is electron transfer from Ru to Fe, and the electronic interaction facilitates the reduction of both Ru and Fe species. When used in combination with Amberlyst-15, the Ru-6.3FeOx/AC catalyst afforded the best performance with a 1,4-PeD yield of 86%; by contrast, Ru/AC free of FeOxonly gave levulinic acid as the major product, demonstrating the key role of the acid/metal balance in the one-pot conversion of furfural to 1,4-PeD. Moreover, such a dual catalyst exhibited excellent durability within 175 h time-on-stream.
Liu, Fei,Liu, Qiaoyun,Qiao, Botao,Su, Yang,Wang, Aiqin,Zhang, Leilei,Zhang, Tao
supporting information
p. 3532 - 3538
(2020/08/28)

Selective Hydrogenation of Xylose to Xylitol over Co/SiO2 Catalysts
Xylose can be selectively converted to xylitol in water, with an optimized yield of 98 %, in the presence of a simple silica supported monometallic cobalt – Co/SiO2 – catalyst. This catalyst displays initial outstanding catalytic properties in a proper solvent, the best results being obtained in pure water. Recyclability studies show a moderate deactivation of the catalyst, while selectivity to xylitol remains almost unchanged after 4 cycles, confirming that this catalyst formulation is very promising for the xylitol production process.
Audemar, Ma?té,Ramdani, Wahiba,Junhui, Tang,Raluca Ifrim, Andreea,Ungureanu, Adrian,Jér?me, Fran?ois,Royer, Sébastien,de Oliveira Vigier, Karine
p. 1973 - 1978
(2020/03/23)

A magnetic CoRu-CoO: X nanocomposite efficiently hydrogenates furfural to furfuryl alcohol at ambient H2 pressure in water
A one-pot synthesized CoRu-CoOX nanocomposite was reported as a magnetically recoverable catalyst for selective hydrogenation of furfural to furfuryl alcohol in water at ambient H2 pressure.
Cao, Qiue,Fang, Wenhao,Lu, Yaowei,Wang, Yongxing
p. 3765 - 3768
(2020/04/10)

Selective Hydrogenation of Biomass-Derived Furfural: Enhanced Catalytic Performance of Pd?Cu Alloy Nanoparticles in Porous Polymer
Here, the development of a new catalyst is reported for the selective furfural (FF) hydrogenation to furfuryl alcohol (FA) based on about 7 nm sized Pd?Cu alloy nanoparticles (NPs) formed in inexpensive, commercially available micro/mesoporous hypercrosslinked polystyrene (HPS). A comparison of the catalytic properties of as-synthesized and reduced (denoted “r”) catalysts as well as Pd?Cu alloy and monometallic palladium NPs showed a considerable enhancement of the catalytic performance of Pd?Cu/HPS-r compared to other catalysts studied, resulting in about 100 percent FF conversion, 95.2 percent selectivity for FA and a TOF of 1209 h?1. This was attributed to the enrichment of the NP surface with copper atoms, disrupting the furan ring adsorption, and to the presence of both zerovalent and cationic palladium and copper species, resulting in optimal hydrogen and FF adsorption. These factors along with exceptional stability of the catalyst in ten consecutive catalytic cycles make it highly promising in practical applications.
Salnikova, Ksenia E.,Larichev, Yurii V.,Sulman, Esther M.,Bykov, Alexey V.,Sidorov, Alexander I.,Demidenko, Galina N.,Sulman, Mikhail G.,Bronstein, Lyudmila M.,Matveeva, Valentina G.
p. 1697 - 1703
(2020/07/20)

Polyether Natural Product Inspired Cascade Cyclizations: Autocatalysis on π-Acidic Aromatic Surfaces
Anion-π catalysis functions by stabilizing anionic transition states on aromatic π surfaces, thus providing a new approach to molecular transformation. The delocalized nature of anion–π interactions suggests that they serve best in stabilizing long-distance charge displacements. Aiming therefore for an anionic cascade reaction that is as charismatic as the steroid cyclization is for conventional cation-π biocatalysis, reported here is the anion-π-catalyzed epoxide-opening ether cyclizations of oligomers. Only on π-acidic aromatic surfaces having a positive quadrupole moment, such as hexafluorobenzene to naphthalenediimides, do these polyether cascade cyclizations proceed with exceptionally high autocatalysis (rate enhancements kauto/kcat >104 m?1). This distinctive characteristic adds complexity to reaction mechanisms (Goldilocks-type substrate concentration dependence, entropy-centered substrate destabilization) and opens intriguing perspectives for future developments.
Hao, Xiaoyu,Matile, Stefan,Paraja, Miguel
supporting information
p. 15093 - 15097
(2020/04/09)

Controllable chemoselective hydrogenation of furfural by PdAg/C bimetallic catalysts under ambient operating conditions: An interesting Ag switch
Hydrogenation of furfural to value-added chemical products is largely hindered by its multiple reaction pathways and complicated product distribution. Thus, to selectively achieve the desired products, catalysts with precise catalytic properties are highly required. Herein, a series of PdAg bimetallic nanoparticles (NPs) of similar size and tunable composition supported on activated carbon (Pd4Ag1/C, Pd2Ag1/C, Pd1Ag1/C and Pd2Ag3/C) were synthesized in a controlled manner and applied in the selective hydrogenation of furfural. Interestingly, an obvious composition-dependent catalytic performance was observed: upon incrementally increasing the proportion of Ag in PdAg NPs, the hydrogenation selectivity can transform from tetrahydrofurfuryl alcohol (sel. 94% for Pd4Ag1/C) to furfuryl alcohol (sel. 95% for Pd1Ag1/C) with nearly complete conversion (99%) of furfural. DFT calculations revealed that the adsorption free energy of in situ generated furfuryl alcohol on Pd(111) surface is inversely proportional correlated with the Ag content in PdAg bimetallic NPs, which accounts for the alteration of chemoselectivity. Importantly, the present study is the first demonstration of composition-induced selectivity reversal for the hydrogenation of furfural under ambient conditions (25 °C, 0.1 MPa H2).
Wu, Zhi-Lei,Wang, Jian,Wang, Shuo,Zhang, Ya-Xin,Bai, Guo-Yi,Ricardez-Sandoval, Luis,Wang, Gui-Chang,Zhao, Bin
p. 1432 - 1442
(2020/03/11)

Ruthenium on phosphorous-modified alumina as an effective and stable catalyst for catalytic transfer hydrogenation of furfural
Supported ruthenium was used in the liquid phase catalytic transfer hydrogenation of furfural. To improve the stability of Ru against leaching, phosphorous was introduced on a Ru/Al2O3 based catalyst upon impregnation with ammonium hypophosphite followed by either reduction or calcination to study the effect of phosphorous on the physico-chemical properties of the active phase. Characterization using X-ray diffraction, solid state 31P nuclear magnetic resonance spectroscopy, X-ray absorption spectroscopy, temperature programmed reduction with H2, infrared spectroscopy of pyridine adsorption from the liquid phase and transmission electron microscopy indicated that phosphorous induces a high dispersion of Ru, promotes Ru reducibility and is responsible for the formation of acid species of Br?nsted character. As a result, the phosphorous-based catalyst obtained after reduction was more active for catalytic transfer hydrogenation of furfural and more stable against Ru leaching under these conditions than a benchmark Ru catalyst supported on activated carbon.
Campisi, Sebastiano,Ferri, Davide,Fovanna, Thibault,Kambolis, Anastasios,Kr?cher, Oliver,Nachtegaal, Maarten,Peng, Gael,Rentsch, Daniel,Villa, Alberto
p. 11507 - 11516
(2020/04/03)

Pd(II) and Pt(II) catalysed selective synthesis of furfuryl alcohol: Solvent effects and insights into the mechanism
Selective conversion of furfural to furfural alcohol, a bio-based commodity chemical with applications in the agriculture, metal casting and polymer industries is presented. Pd(II) and Pt(II) complexes were synthesized and characterized using multi-nuclear magnetic resonance spectroscopy, infrared spectroscopy, high resolution electrospray ionisation mass spectrometry as well as elemental analysis. These complexes were found to serve as excellent pre-catalysts for furfural alcohol synthesis with excellent conversion and selectivity (>99%), more so under solvent-free conditions via transfer hydrogenation method. Catalysts C1 and C5 also showed enhanced activity and selectivity as pre-catalysts for the hydrogenation of furfural using formic acid as a hydrogen carrier. The platinum catalyst C5 was recycled twice (with consistent activity and selectivity), and proved to function as a molecular catalyst as evidenced by mercury poisoning experiments. In situ NMR studies were performed using C5 culminated in the proposition of plausible reaction mechanism, and a likely catalytically active species has been identified with the aid of 1H and 31P{1H} NMR.
Makhubela, Banothile C. E.,Matsinha, Leah C.,Moyo, Pamela S.
(2020/07/08)

Colloidal and Nanosized Catalysts in Organic Synthesis: XXIV. Study of Hydrogenation of Furan and Its Derivatives in the Presence of MgO-Supported Nickel and Cobalt Nanoparticles
Abstract: The processes of hydrogenation of furan and its derivatives (2-methylfuran, furfuryl alcohol, and furfural) in plug-flow type reactor under atmospheric hydrogen pressure at 20–220°С in the presence of supported nickel nanoparticles prepared via chemical reduction have been investigated. It has been found that nickel nanoparticles supported on magnesium oxide surface are the most reactive and stable under the considered conditions. This catalyst allows the corresponding hydrogenation products with 100percent yield and complete conversion of the substrate.
Gendler, T. A.,Mokhov, V. M.,Nebykov, D. N.,Popov, Yu. V.,Shemet, V. V.,Shirkhanyan, P. M.
p. 931 - 935
(2020/07/27)

Dual-Site-Mediated Hydrogenation Catalysis on Pd/NiO: Selective Biomass Transformation and Maintenance of Catalytic Activity at Low Pd Loading
Creating a new chemical ecosystem based on platform chemicals derived from waste biomass has significant challenges: catalysts need to be able to convert these highly functionalized molecules to specific target chemicals and they need to be economical - not relying on large quantities of precious metals - and maintain activity over many cycles. Herein, we demonstrate how Pd/NiO is able to direct the selectivity of furfural hydrogenation and maintain performance at low Pd loading by a unique dual-site mechanism. Sol-immobilization was used to prepare 1 wt % Pd nanoparticles supported on NiO and TiO2, with the Pd/NiO catalyst showing enhanced activity with a significantly different selectivity profile; Pd/NiO favors tetrahydrofurfuryl alcohol (72%), whereas Pd/TiO2 produces furfuryl alcohol as the major product (68%). Density functional theory studies evidenced significant differences on the adsorption of furfural on both NiO and Pd surfaces. On the basis of this observation we hypothesized that the role of Pd was to dissociate hydrogen, with the NiO surface adsorbing furfural. This dual-site hydrogenation mechanism was supported by comparing the performance of 0.1 wt % Pd/NiO and 0.1 wt % Pd/TiO2. In this study, the 0.1 and 1 wt % Pd/NiO catalysts had comparable activities, whereas there was a 10-fold reduction in performance for 0.1 wt % Pd/TiO2. When TiO2 is used as the support, the Pd nanoparticles are responsible for both hydrogen dissociation and furfural adsorption and the activity is strongly correlated with the effective metal surface area. This work has significant implications for the upgrading of bioderived feedstocks, suggesting alternative ways for promoting selective transformations and reducing the reliance on precious metals.
Botton, Gianluigi A.,Campisi, Sebastiano,Chan-Thaw, Carine E.,Chinchilla, Lidia E.,Chutia, Arunabhiram,Dimitratos, Nikolaos,Mohammed, Khaled M. H.,Villa, Alberto,Wells, Peter P.
p. 5483 - 5492
(2020/09/02)

Efficient one-pot conversion of furfural into 2-methyltetrahydrofuran using non-precious metal catalysts
2-methyltetrahydrofuran, a biomass-derived chemical, is an important solvent with broad applications in organic chemistry. In this study, one-pot conversion of furfural into 2-methyltetrahydrofuran over non-precious metal catalysts was achieved by two-stage packing in a single reactor. The first stage converted furfural into 2-methylfuran over Co-based catalysts, and the second stage converted 2-methylfuran into 2-methyltetrahydrofuran over Ni-based catalysts. In order to reveal the reaction pathway and mechanism of this process, the hydrogenation reactions of 2-methylfuran, furfuryl alcohol, and tetrahydrofurfuryl alcohol were also carefully investigated. It is discovered that the conversion of furfural into 2-methylfuran could be catalyzed by Lewis acid sites, which was confirmed by a correlation between 2-methylfuran production rate and Lewis acid site density. Also, a mechanism on the direct conversion of furfural into 2-methylfuran without forming furfuryl alcohol as the intermediate is proposed. The experimental results of 2-methylfuran, furfuryl alcohol, and tetrahydrofurfuryl alcohol hydrogenation/hydrodeoxygenation over various catalysts provided valuable information on the future design of 2-methyltetrahydrofuran catalyst.
Jia, Xinxin,Li, Cuiqing,Liu, Ping,Song, Yongji,Sun, Luyang,Wang, Hong,Zhang, Chen,Zhang, Wei
(2020/04/29)

Method for preparing 5-hydroxymethyldihydrofuran-2-one by taking furfural as raw material
The invention discloses a method for preparing 5-hydroxymethyldihydrofuran-2-one by using furfural as a raw material, and relates to a preparation method of an organic chemical raw material. The method is as follows: furfural is used as a raw material, ethanol is used as a solvent, a Raney nickel catalyst is used, and tetrahydrofurfuryl alcohol is prepared by catalytic hydrogenation reduction; gamma-Al2O3 is taken as a carrier, cerium nitrate and silver nitrate are taken as raw materials, and an Ag/CeO2/Gamma-Al2O3 catalyst is prepared by adopting an impregnation method, a roasting method anda natural cooling method; and the prepared tetrahydrofurfuryl alcohol is used as a raw material, the prepared Ag/CeO2/gamma-Al2O3 catalyst is adopted, and oxygen is introduced for a reaction to obtain5-hydroxymethyl dihydrofuran-2-one. The method is beneficial to improving the product selectivity; the catalyst is prepared by adopting a dipping-roasting method, the method is simple, the dispersityof active metal elements is good, and the product selectivity is high; and the product 5-hydroxymethyldihydrofuran-2-one has hydroxyl, furan ring and keto functional groups, is a raw material for synthesizing a plurality of antiviral, anticancer and anti-AIDS medicines, and has the advantages of high added value, high economic benefit and high social benefit.
-
Paragraph 0018-0021

(2020/07/02)

Selective hydrogenation of aromatic furfurals into aliphatic tetrahydrofurfural derivatives
Tetrahydrofurfural (THFF) and 5-hydroxymethyltetrahydro-2-furaldehyde (5-HMTHFF) are important chemicals. Synthesis of THFF and 5-HMTHFF from the selective hydrogenation of furfural (FF) and 5-hydroxymethylfurfural (HMF) is highly desirable. However, it is a great challenge to hydrogenate furanyl rings while keeping CO intact. Herein, we found that Pd/LDH-MgAl-NO3 could efficiently catalyze the hydrogenation of FF to THFF and HMF to 5-HMTHFF in water. At near complete conversion of FF and HMF, the selectivities of THFF and 5-HMTHFF could reach 92.6% and 83.7%, respectively. A series of control experiments showed that both the LDH-MgAl-NO3 support and water solvent played an important role in the unusual performance of the catalytic system. The hydrogenation of the furanyl ring occurred on the surface of Pd. Water prohibited the hydrogenation of the CO group, and the special nature of LDH-MgAl-NO3 prevented hydrogenation of the CO group on the support by the hydrogen spillover. Thus, the furanyl ring was selectively hydrogenated, and high selectivity of the desired product was successfully achieved. As far as we know, efficient hydrogenation of FF to THFF or HMF to 5-HMTHFF has not been reported. This work opens the way to selectively hydrogenate the furanyl ring while keeping CO in the same molecule unchanged. This journal is
Chen, Bingfeng,Han, Buxing,Li, Shaopeng,Liu, Huizhen,Shen, Xiaojun,Wang, Yanyan,Yang, Youdi
supporting information
p. 4937 - 4942
(2020/11/07)

C-2 auxiliaries for stereoselective glycosylation based on common additive functional groups
The stereoselective introduction of the glycosidic bond is one of the main challenges in chemical oligosaccharide synthesis. Stereoselective glycosylation can be achieved using neighbouring group participation of a C-2 auxiliary or using additives, for example. Both methods aim to generate a defined reactive intermediate that reacts in a stereoselective manner with alcohol nucleophiles. This inspired us to develop new C-2 auxiliaries based on commonly used additive functionalities such as ethers, phosphine oxides and tertiary amides. Good 1,2-trans-selectivity was observed for the phosphine oxide and amide-based auxiliaries expanding the toolbox with new auxiliaries for stereoselective glycosylation reactions.
Boltje, Thomas J.,De Kleijne, Frank F. J.,Moons, Sam J.,White, Paul B.
p. 1165 - 1184
(2020/02/22)

Site- And enantiodifferentiating C(sp3)-H oxidation enables asymmetric access to structurally and stereochemically diverse saturated cyclic ethers
A manganese-catalyzed site- and enantiodifferentiating oxidation of C(sp3)-H bonds in saturated cyclic ethers has been described. The mild and practical method is applicable to a range of tetrahydrofurans, tetrahydropyrans, and medium-sized cyclic ethers with multiple stereocenters and diverse substituent patterns in high efficiency with extremely efficient site- and enantiodiscrimination. Late-stage application in complex biological active molecules was further demonstrated. Mechanistic studies by combined experiments and computations elucidated the reaction mechanism and origins of stereoselectivity. The ability to employ ether substrates as the limiting reagent, together with a broad substrate scope, and a high level of chiral recognition, represent a valuable demonstration of the utility of asymmetric C(sp3)-H oxidation in complex molecule synthesis.
Liu, Lei,Sun, Shutao,Yang, Yiying,Zhang, Dongju,Zhao, Ran
supporting information
p. 19346 - 19353
(2020/12/01)

Hydrogenation of furfural by noble metal-free nickel modified tungsten carbide catalysts
Nickel-tungsten carbide catalysts convert furfural to high value products in a liquid phase catalytic reaction. The product distribution depends on the solvent and the Ni-W-ratio of the catalyst. In isopropyl alcohol a combination of Ni and WxC enables the opening of the furan ring to yield 1,2-pentanediol. Nickel accelerates the tungsten oxide reduction in the tungsten carbide catalyst synthesis and facilitates the carbon insertion. Nickel modified tungsten carbide is a promising, noble metal-free catalyst system for the upgrading of furfural based renewable resources. Its preparation is facilitated compared to unmodified tungsten carbide catalysts.
Bretzler, Patrick,Huber, Michael,K?hler, Klaus,Nickl, Simon
p. 27323 - 27330
(2020/09/01)

Hydrogenolysis of tetrahydrofuran-2-carboxylic acid over tungsten-modified rhodium catalyst
Catalysts for reduction of tetrahydrofuran-2-carboxylic acid (THFCA), which can be synthesized from furfural via oxidation and hydrogenation, were explored among the combinations of noble metal and reducible metal oxide supported on SiO2. Rh-WOx/SiO2 catalysts showed activity in C-O hydrogenolysis at 2-position of THFCA (to δ-valerolactone and 5-hydroxyvaleric acid) and higher yield ratio of these C-O hydrogenolysis products to carboxylic acid hydrogenation products than other bimetallic catalysts. The activity of Rh-WOx/SiO2 catalysts was highest at W/Rh = 0.25 mol/mol. XRD, TPR, CO adsorption and XAFS characterizations showed that the Rh-WOx/SiO2 (W/Rh = 0.25) catalyst contained Rh metal particles with surface modification with isolated W2+ oxide species. The mechanism that hydride-like species formed on Rh atom attacks the C atom at the α-position (2-position) of adsorbed carboxylate on W atom is proposed based on the similar kinetics and similar catalyst structure to Rh-MOx/SiO2 (M = Re, Mo) which is known to be active in THFA hydrogenolysis to 1,5-pentanediol.
Asano, Takehiro,Nakagawa, Yoshinao,Tamura, Masazumi,Tomishige, Keiichi
(2020/07/04)