623-15-4Relevant academic research and scientific papers
Aldol condensation of furfural and acetone on layered double hydroxides
Liu, Huihui,Xu, Wenjie,Liu, Xiaohui,Guo, Yun,Guo, Yanglong,Lu, Guanzhong,Wang, Yanqin
, p. 75 - 80 (2010)
The Aldol condensation of furfural (Fur) with acetone (Ac) to 4-(2-Furyl)-3-buten-2-one (FAc) is one of the most important processes in the aqueous-reforming of oxygen-containing biomass derivatives and has been carried out in the presence of solid-base catalysts, calcined-rehydrated Layered Double Hydroxides (LDH). The Mg-Al Layered Double Hydroxides has been prepared by the coprecipitation, calcination and regeneration from mixed oxides by rehydration. The catalyst prepared with different Mg/Al molar ratios showed different catalytic performance and the best catalyst was with the Mg/Al molar ratio of 2.5. Phenol adsorption showed that the best catalyst had the largest numbers of accessible basic sites. The appropriate rehydration temperature and time for mixed oxides obtained by calcination were also investigated. The Mg-Al LDH catalysts can be regenerated by calcination at 773 K and rehydration in decarbonate water, but the regeneration is complex and incomplete. In addition, the catalyst calcined at high temperature also had activity, which was attributed to the formation of the Mg-Al spinels.
Production of a renewable 1,3-diene containing a functional group from a furfural-acetone adduct in a fixed-bed reactor
Qi, Yanlong,Liu, Shijun,Cui, Long,Dai, Quanquan,He, Jianyun,Dong, Wei,Bai, Chenxi
, p. 3911 - 3919 (2019)
The synthesis of functionalized 1,3-dienes has received increasing attention due to their importance in the practical development of high-performance elastomers. In the present work, furfural and acetone, acting as renewable feedstocks, are first employed to produce a functionalized 1,3-diene containing a furan group (1-(2-furyl)-1,3-butadiene, F-diene). After selective hydrogenation of the CO group, the aldol adduct (4-(2-furanyl)-3-buten-2-ol, FAH) shows a nearly complete conversion, with an excellent selectivity (as high as 92%) towards F-diene over ceria-based catalysts in a fixed bed. BET, TEM, XRD, XPS, Raman, TPD, TPR and TGA were conducted to identify the relationship between the catalytic performance and catalyst structure. A plausible reaction pathway for the dehydration of FAH over ceria-based catalysts was proposed using a radical mechanism, which suggested the importance of the Ce4+-Ce3+ redox cycle for the dehydration of FAH to F-diene. Furthermore, the ceria-based catalysts exhibited a notable carbon resistance.
Aldol condensation of furfural and acetone on zeolites
Kikhtyanin, Oleg,Kelbichová, Vendula,Vitvarová, Dana,Kub?, Martin,Kubi?ka, David
, p. 154 - 162 (2014)
Zeolites of different structural types were used as catalysts for aldol condensation of furfural and acetone in batch reaction conditions at T = 20-100 C and time 0-24 h. To establish a relation between physico-chemical and catalytic properties of microporous materials, the samples were characterized by SEM, N2 adsorption, FTIR and TGA. It was found that the acidic solids possessed appreciable activity in the reaction and resulted in a formation of products of aldehyde-ketone interaction. Nevertheless, furfural conversion decreased rapidly due to coke formation inside zeolite pores. Simultaneously with a general route of the reaction observed for basic catalysts, dimerization of the condensation product on acidic sites occurred. It was supposed that catalytic behavior of zeolites considerably affected by their both structural and textural properties. Experiments with re-used samples showed that zeolites totally restored their activity and selectivity after calcination at 530 C.
Production of liquid fuel intermediates from furfural via aldol condensation over La2O2CO3-ZnO-Al2O3 catalyst
Fang, Zhen,Kong, Xiao,Lei, Hanwu,Li, Lu-ping,Wei, Xiao-jie
, (2020/11/12)
Aldol condensation of furfural with acetone over basic catalysts allows the production of furanic adducts 4-(2-furyl)-3-buten-2-one (FAc, C8) and 1,5-di-2-furanyl-1,4-pentadien-3-one (F2Ac, C13)) that can be transformed into high-quality diesel
Synthesis of jet fuel intermediates via aldol condensation of biomass-derived furfural with lanthanide catalyst
Cong, Wen-Jie,Fang, Zhen,Kong, Xiao,Li, Lu-ping
, (2021/10/01)
Jet fuel precursors (4-(2-furyl)-3-buten-2-one (FAc) and 1,5-di-2-furanyl-1,4-pentadien-3-one (F2Ac)) can be produced from aldol condensation between furfural and acetone over basic catalysts. However, there is still a need to develop efficient alkaline catalysts and understand the role of alkaline sites. In this work, La2O2CO3-Al2O3 catalyst was successfully prepared by coprecipitation and the effect of preparation conditions on the properties and catalytic performance was investigated. Experiments showed that La2O2CO3 and La2O3 were formed after calcination, and the activity was greatly improved by the introduction of La2O2CO3. At higher coprecipitation pH, rod-shaped La2O2CO3 was formed, which exhibits higher exposure of basic La3+-O2? sites and shows good performance in aldol condensation reactions. The catalytic performance of La2O2CO3-Al2O3 in aldol condensation of furfural with acetone was also evaluated and compared with that of Al2O3, La2O3, La2O3-Al2O3, La(OH)?/Al2O3 and La2O2CO3/Al2O3. A total conversion of furfural can be realized with F2Ac yield of 67.8% at a furfural/acetone ratio of 1/1 and 90 °C, with a FAc yield of 25.8% at the same time. The deactivation mechanism of the La2O2CO3-Al2O3 catalyst was also studied.
Polysubstituted Indole Synthesis via Palladium/Norbornene Cooperative Catalysis of Oxime Esters
Huang, Liangbin,Jiang, Huanfeng,Lin, Haojiang,Liu, Jiechun
supporting information, (2022/01/20)
Polysubstituted indoles are prevalent in pharmaceuticals, agrochemicals, and organic materials. Presented herein is the fact that polyfunctionalized indoles can be efficiently constructed from easily accessible oxime esters and aryl iodides, involving a palladium/norbornene synergistic synthesis. The reaction is enabled by a unique class of electrophiles in palladium/norbornene cooperative catalysis, which are oxime esters derived from simple ketone. The broad substrate scope and high functional group tolerance could make this method attractive for the synthesis of polysubstituted indoles.
Rate dependence on inductive and resonance effects for the organocatalyzed enantioselective conjugate addition of alkenyl and alkynyl boronic acids to β-indolyl enones and β-pyrrolyl enones
Boylan, Amy,Li, Jian-Yuan,Lundy, Brian J.,May, Jeremy A.,Nguyen, Thien S.,Sundstrom, Sasha,Vallakati, Ravikrishna
, (2021/06/16)
Two key factors bear on reaction rates for the conjugate addition of alkenyl boronic acids to heteroaryl-appended enones: the proximity of inductively electron-withdrawing heteroatoms to the site of bond formation and the resonance contribution of available heteroatom lone pairs to stabilize the developing positive charge at the enone β-position. For the former, the closer the heteroatom is to the enone β-carbon, the faster the reaction. For the latter, greater resonance stabilization of the benzylic cationic charge accelerates the reaction. Thus, reaction rates are increased by the closer proximity of inductive electron-withdrawing elements, but if resonance effects are involved, then increased rates are observed with electron-donating ability. Evidence for these trends in isomeric substrates is presented, and the application of these insights has allowed for reaction conditions that provide improved reactivity with previously problematic substrates.
Highly efficient catalytic transfer hydrogenation of furfural over defect-rich amphoteric ZrO2with abundant surface acid-base sites
Zhu, Zekun,Yang, Lingling,Ke, Changxuan,Fan, Guoli,Yang, Lan,Li, Feng
, p. 2616 - 2626 (2021/03/03)
Currently, the catalytic transformation and utilization of biomass-derived compounds are of great importance to the alleviation of environmental problems and sustainable development. Among them, furfural alcohol derived from biomass resources has been found to be one of the most prospective biomass platforms for high-value chemicals and biofuels. Herein, high-surface-area ZrO2 with abundant oxygen defects and surface acid-base sites was synthesized and used as a heterogeneous catalyst for the catalytic transfer hydrogenation of furfural into furfural alcohol using alcohol as a hydrogen donor. The as-synthesized ZrO2 exhibited excellent catalytic performance with 98.2% FA conversion and 97.1% FOL selectivity, even comparable with that of a homogeneous Lewis acid catalyst. A series of characterization studies and experimental results revealed that acid sites on the surface of ZrO2 could adsorb and activate the CO bond in furfural and base sites could facilitate the formation of alkoxide species. The synergistic effect of surface acid-base sites affords a harmonious environment for the reaction, which is crucial for catalytic transfer hydrogenation of furfural with high efficiency. Furthermore, the as-prepared ZrO2 catalyst also exhibited a potential application for the efficient catalytic transfer hydrogenation of a series of biomass-derived carbonyl compounds. This journal is
The influence of long-term exposure of Mg–Al mixed oxide at ambient conditions on its transition to hydrotalcite: The long-term aging of Mg–Al mixed oxide
Bábelová, Monika,Hájek, Martin,Kocík, Jaroslav,Strejcová, Kate?ina,Ti?ler, Zdeněk,Velvarská, Romana
, (2021/09/08)
The paper is focused on the study of long-term aging of Mg–Al mixed oxides, which causes the rebuilding of the hydrotalcite layered structure in the presence of humidity. The novelty consists in the description of influence during the long-term aging (6 m
Bi-Functional Magnesium Silicate Catalyzed Glucose and Furfural Transformations to Renewable Chemicals
Kumar, Abhinav,Srivastava, Rajendra
, p. 4807 - 4816 (2020/08/24)
Bio-refinery is attracting significant interest to produce a wide range of renewable chemicals and fuels from biomass that are alternative to fossil fuel derived petrochemicals. Similar to petrochemical industries, bio-refinery also depends on solid zeolite catalysts. Acid-base catalysis plays pivotal role in producing a wide range of chemicals from biomass. Herein, the Mg framework substituted MTW zeolite is synthesized and explored in the valorisation of glucose and furfural. Bi-functional (acidic and basic) characteristics are confirmed using pyridine adsorbed FT?IR analysis and NH3 and CO2 temperature-programmed desorption techniques. Textural properties and morphological information are retrieved from N2-sorption, X-ray photoelectron spectroscopy, and electron microscopy. The activity of the catalyst is demonstrated in the selective isomerisation of glucose to fructose in ethanol. Glucose is converted to methyl lactate in high yield using the same catalyst. Further, the bi-functional activity of this catalyst is demonstrated in the production of fuel precursor by the reaction of furfural and isopropanol. Mg?MTW zeolite exhibits excellent activity in the production of all these chemicals and fuel derivative. The catalyst exhibits no significant loss in the activity even after five recycles. One simple catalyst affording three renewable synthetic intermediates from glucose and furfural will attract significant attention to catalysis researchers and industrialists.
