scholarly journals Highly Selective Reduction of Bio-Based Furfural to Furfuryl Alcohol Catalyzed by Supported KF with Polymethylhydrosiloxane (PMHS)

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Zhaozhuo Yu ◽  
Weibo Wu ◽  
Hu Li ◽  
Song Yang
Keyword(s):  
Catalytic System ◽  
Furfuryl Alcohol ◽  
Low Cost ◽  
Selective Reduction ◽  
Reusable Catalyst ◽  
Acid Base ◽  
Reaction Conditions ◽  
Mild Conditions ◽  
Pore Blocking ◽  
Icp Ms

Hydrogenation of bio-based furfural (FUR) to furfuryl alcohol (FFA) is tremendously expanding the application of biomass in many industries such as resins, biofuels, and pharmaceuticals. However, mass manufacture of FFA from FUR is restrained by strict requirements of reaction conditions and expensive catalysts. In this work, an economical and benign catalytic system, containing an easily prepared and reusable catalyst 5 wt.% KF/ZrO2 and a low-cost hydrogen source polymethylhydrosiloxane (PMHS), was developed to be efficient for the hydrogenation of FUR to high-value FFA under mild conditions. The catalyst reactivity was found to be remarkably influenced by the support acid-base properties and KF loading doge. In the presence of 5 wt.% KF/ZrO2, a high FFA yield of 97% and FUR conversion of 99% could be obtained at 25°C in just 0.5 h, which was superior to those attained with other tested catalysts. The KF/ZrO2 catalyst could be recycled at least five times, with the FFA yield slightly decreasing from 97% to 71%. The spare decrease in FFA yield is possibly attributed to the catalyst pore blocking, as clarified by SEM, BET, XPS, and ICP-MS measurements of the fresh and reused catalysts.

scholarly journals Polystyrene-supported aluminum chloride as an efficient and reusable catalyst for condensation of indole with various carbonyl compounds

2010 ◽  
Vol 75 (4) ◽  
pp. 423-431 ◽  
Author(s):  
Bahman Tamami ◽  
Nasrolahi Shirazi ◽  
Parvanak Borujeni
Keyword(s):  
Aluminum Chloride ◽  
Carbonyl Compounds ◽  
Low Cost ◽  
Reaction Times ◽  
Reusable Catalyst ◽  
Reaction Conditions ◽  
Crosslinked Polystyrene ◽  
Aldehydes And Ketones ◽  
Polymeric Catalyst ◽  
Work Up

Crosslinked polystyrene-supported aluminum chloride (Ps-AlCl3) is a stable, recyclable and environmental friendly heterogeneous catalyst for the condensation of indole with aldehydes and ketones to afford bis-indolylmethanes. In addition, (Ps-AlCl3) shows satisfactory selectivity in the reaction of mixtures of an aldehyde and a ketone with indole. Although AlCl3 is a water sensitive, corrosive and environmentally harmful compound, Ps-AlCl3 is a stable and water-tolerant species. The mild reaction conditions, short reaction times, easy work-up, high to excellent yields, chemoselectivity, reuse of the catalyst for at least ten times without significant change in its catalytic activity, low cost, and easy preparation and handling of the polymeric catalyst are obvious advantages of the present method.

scholarly journals Cs2CO3/[bmim]Br as an Efficient, Green, and Reusable Catalytic System for the Synthesis of N-Alkyl Derivatives of Phthalimide under Mild Conditions

2008 ◽  
Vol 2008 ◽  
pp. 1-4 ◽  
Author(s):  
Alireza Hasaninejad ◽  
Abdolkarim Zare ◽  
Ahmad Reza Moosavi-Zare ◽  
Fatemeh Khedri ◽  
Rahimeh Rahimi ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Catalytic System ◽  
Reaction Times ◽  
Catalytic Amount ◽  
Conjugate Addition ◽  
Reaction Conditions ◽  
Mild Conditions ◽  
Alkyl Derivatives ◽  
High Yields ◽  
Derivatives Of

Aza-conjugate addition of phthalimide to α,β-unsaturated esters efficiently achieves in the presence of catalytic amount of Cs2CO3 and ionic liquid 1-butyl-3-methylimidazolium bromide ([bmim]Br) under mild reaction conditions (70°C) to afford N-alkyl phthalimides in high yields and relatively short reaction times.

scholarly journals Greener synthesis of dimethyl carbonate from carbon dioxide and methanol using a tunable ionic liquid catalyst

2019 ◽  
Vol 17 (1) ◽  
pp. 1252-1265
Author(s):  
Atul A. Pawar ◽  
Avinash A. Chaugule ◽  
Hern Kim
Keyword(s):  
Catalytic System ◽  
Oxide Catalyst ◽  
Dimethyl Carbonate ◽  
Raw Materials ◽  
Absorption Capacity ◽  
High Thermal Stability ◽  
Acid Base ◽  
Reaction Conditions ◽  
Optimum Reaction ◽  
Greener Synthesis

AbstractSeveral types of ionic liquids (ILs) performance towards dimethyl carbonate (DMC) synthesis using cheap reactant (methanol) and waste CO2 which is abundantly available in the environment are discussed. We synthesized ILs with cheap raw materials such as ethylene glycol. The main aim of this study is to synthesize efficient catalysts for the production of profitable fuel additives. ILs show high thermal stability, less viscosity, and low vapor pressure. In addition, some ILs have high CO2 absorption capacity due to moderate acid-base properties. These ILs reversibly capture more CO2 which is more efficient towards mass transport of methanol at optimum reaction conditions which enhance the DMC yield. This catalytic system is easily reusable for several reactions without decreased performance under the same reaction conditions. These reaction conditions had an effect on the synthesis of DMC. Temperature, pressure, IL loading, and IL/DMAP ratio were fine tuned. We propose a mechanism which the reaction may follow. The synthesized ILs required moderate reaction conditions and reduce waste gases (CO2) from the environments as they have high CO2 absorption capacity compared to the metal oxide catalyst. Therefore, this catalytic system helps and gives new direction to synthesize new catalyst for other application.

One-pot preparation of β-amido ketones/esters in a three-component condensation reaction using magnesium hydrogensulfate as an effective and reusable catalyst

2008 ◽  
Vol 86 (5) ◽  
pp. 376-383 ◽  
Author(s):  
Hamid Reza Shaterian ◽  
Asghar Hosseinian ◽  
Majid Ghashang
Keyword(s):  
Room Temperature ◽  
Acetyl Chloride ◽  
Condensation Reaction ◽  
Reusable Catalyst ◽  
Reaction Conditions ◽  
One Pot ◽  
Green Catalyst ◽  
Mild Conditions ◽  
Aryl Aldehyde ◽  
Ketone Ester

A one-pot, three-component condensation of an aryl aldehyde, an enolizable ketone or β-keto ester, acetyl chloride, and acetonitrile or benzonitrile in the presence of magnesium hydrogensulfate as an active, recoverable, and reusable green catalyst is described for the synthesis of β-amido ketones/esters at room temperature. The key features of this methodology are simplicity, mild reaction conditions, and high to excellent yields.Key words: multi-component reaction, magnesium hydrogensulfate, heterogeneous catalyst, β-amido ketone/ester, mild conditions.

Synthesis of 11-hydroxylated androstane derivatives

1980 ◽  
Vol 45 (6) ◽  
pp. 1845-1849 ◽  
Author(s):  
Jan Fajkoš ◽  
Jiří Joska
Keyword(s):  
Selective Reduction ◽  
Reaction Conditions ◽  
Androstane Derivatives

Reaction conditions for selective reduction of 3- and 17-oxo groups are described and applied to syntheses of 11-hydroxylated derivatives.

Practical allylation with unactivated allylic alcohols under mild conditions

2021 ◽  
Author(s):  
Shuangshuang Li ◽  
Ju Qiu ◽  
Bowen Li ◽  
Zuolian Sun ◽  
Peizhong Xie ◽  
...  
Keyword(s):  
Proton Transfer ◽  
Catalytic System ◽  
Allylic Alcohols ◽  
Mild Conditions ◽  
Accelerate Proton

A practical palladium/calcium catalytic system was developed for dehydrative allylation concerning unactivated allylic alcohols. EtOH solvent with H2O additive was identified as powerful media to accelerate proton transfer. That catalytic...

Imidazole-based Cu(i)-catalyzed click polymerization of diazides and diynes under mild conditions

2021 ◽  
Author(s):  
Baixue Li ◽  
Jia Wang ◽  
Anjun Qin ◽  
Ben Zhong Tang
Keyword(s):  
Reaction Conditions ◽  
Mild Conditions ◽  
Click Polymerization

An efficient imidazole-based Cu(i)-catalyzed azide–alkyne click polymerization under mild reaction conditions was developed.

scholarly journals Photocatalytic three-component asymmetric sulfonylation via direct C(sp3)-H functionalization

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shi Cao ◽  
Wei Hong ◽  
Ziqi Ye ◽  
Lei Gong
Keyword(s):  
Asymmetric Catalysis ◽  
Organic Synthesis ◽  
Photochemical Reaction ◽  
Low Cost ◽  
Bioactive Molecules ◽  
Atom Economy ◽  
Mild Conditions ◽  
Wide Range ◽  
Unsaturated Carbonyl Compound ◽  
Direct Functionalization

AbstractThe direct and selective C(sp3)-H functionalization of cycloalkanes and alkanes is a highly useful process in organic synthesis owing to the low-cost starting materials, the high step and atom economy. Its application to asymmetric catalysis, however, has been scarcely explored. Herein, we disclose our effort toward this goal by incorporation of dual asymmetric photocatalysis by a chiral nickel catalyst and a commercially available organophotocatalyst with a radical relay strategy through sulfur dioxide insertion. Such design leads to the development of three-component asymmetric sulfonylation involving direct functionalization of cycloalkanes, alkanes, toluene derivatives or ethers. The photochemical reaction of a C(sp3)-H precursor, a SO2 surrogate and a common α,β-unsaturated carbonyl compound proceeds smoothly under mild conditions, delivering a wide range of biologically interesting α-C chiral sulfones with high regio- and enantioselectivity (>50 examples, up to >50:1 rr and 95% ee). This method is applicable to late-stage functionalization of bioactive molecules, and provides an appealing access to enantioenriched compounds starting from the abundant hydrocarbon compounds.

scholarly journals Ring-Opening Copolymerization of Cyclohexene Oxide and Cyclic Anhydrides Catalyzed by Bimetallic Scorpionate Zinc Catalysts

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1651
Author(s):  
Felipe de la Cruz-Martínez ◽  
Marc Martínez de Sarasa Buchaca ◽  
Almudena del Campo-Balguerías ◽  
Juan Fernández-Baeza ◽  
Luis F. Sánchez-Barba ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Reaction Mechanism ◽  
Catalytic System ◽  
Phthalic Anhydride ◽  
Ring Opening ◽  
High Selectivity ◽  
Zinc Complexes ◽  
Cyclohexene Oxide ◽  
Reaction Conditions ◽  
Cyclic Anhydrides

The catalytic activity and high selectivity reported by bimetallic heteroscorpionate acetate zinc complexes in ring-opening copolymerization (ROCOP) reactions involving CO2 as substrate encouraged us to expand their use as catalysts for ROCOP of cyclohexene oxide (CHO) and cyclic anhydrides. Among the catalysts tested for the ROCOP of CHO and phthalic anhydride at different reaction conditions, the most active catalytic system was the combination of complex 3 with bis(triphenylphosphine)iminium as cocatalyst in toluene at 80 °C. Once the optimal catalytic system was determined, the scope in terms of other cyclic anhydrides was broadened. The catalytic system was capable of copolymerizing selectively and efficiently CHO with phthalic, maleic, succinic and naphthalic anhydrides to afford the corresponding polyester materials. The polyesters obtained were characterized by spectroscopic, spectrometric, and calorimetric techniques. Finally, the reaction mechanism of the catalytic system was proposed based on stoichiometric reactions.

scholarly journals Phytoremediation Potential of Native Herbaceous Plant Species Growing on a Paradigmatic Brownfield Site

2021 ◽  
Vol 232 (7) ◽  
Author(s):  
N. Matanzas ◽  
E. Afif ◽  
T. E. Díaz ◽  
J. R. Gallego
Keyword(s):  
Plant Species ◽  
Contaminated Soils ◽  
Native Species ◽  
Low Cost ◽  
Plantago Lanceolata ◽  
Herbaceous Plant ◽  
Plant Interactions ◽  
Aerial Parts ◽  
Medicago Lupulina ◽  
Icp Ms

AbstractPhytomanagement techniques using native species allow the recovery of contaminated soils at low cost and circumvent the ecological risks associated with the use of non-native species. In this context, a paradigmatic brownfield megasite highly contaminated by As and Pb was sampled in order to analyze soil–plant interactions and identify plant species with phytoremediation potential. A survey was first carried out in a 20-ha area to obtain an inventory of species growing spontaneously throughout the site. We then performed another survey in the most polluted sub-area (1 ha) within the site. Pseudototal concentrations of contaminants in the soil, aerial parts of the plants, and roots were measured by ICP-MS. A detailed habitat classification was done, and a specific index of coverage was applied by means of a 1-year quadrat study in various sampling stations. Results converged in the selection of six herbaceous species (Dysphania botrys, Lotus corniculatus, Lotus hispidus, Plantago lanceolata, Trifolium repens, Medicago lupulina). All of these plants are fast-growing, thereby making them suitable for use in phytostabilization strategies. Furthermore, they are all easy to grow and propagate and are generally self-sustaining. All six plants showed accumulation factors below 1, thus revealing them as pseudomethallophytes and excluders. However, L. hispidus and M. lupulina showed translocation capacity and are considered worthy of further study.

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