628-63-7Relevant academic research and scientific papers
Stable and recyclable MIL-101(Cr)–Ionic liquid based hybrid nanomaterials as heterogeneous catalyst
Hassan, Hassan M.A.,Betiha, Mohamed A.,Mohamed, Shaimaa K.,El-Sharkawy,Ahmed, Emad A.
, p. 385 - 394 (2017)
Br?nsted acidic ionic liquid, N-methyl-2-pyrrolidonium methyl sulfonate ([NMP]+?CH3SO3?) immobilized on MIL-101(Cr) was fabricated by simple impregnation method with a good combination of MIL-101(Cr) and IL species. The worthiness of IL/MIL-101(Cr), as a Br?nsted acid catalyst, has been examined for the esterification of acetic acid with amyl alcohol and Friedel–Crafts acylation of anisole. Our findings demonstrated that IL/MIL-101(Cr) catalyst exhibited distinct catalytic activity with respect to the other catalysts towards the esterification reaction and Friedel–Crafts acylation of anisole. The Br?nsted acidic catalysts loaded on MIL-101(Cr) as a new category of porous materials are probably auspicious heterogeneous catalysts for acid-catalyzed to replace the use of traditional homogeneous catalysts. Furthermore, the catalyst can be easily removed from the reactions mixtures and reuse for posterior reactions, more than six times without any considerable decay in catalytic performance.
Esterification reaction kinetics of acetic acid and n-pentanol catalyzed by sulfated zirconia
Hamerski, Fabiane,Dusi, Giovana Gon?alves,Fernandes dos Santos, Julia Trancoso,da Silva, Vítor Renan,Pedersen Voll, Fernando Augusto,Corazza, Marcos Lúcio
, p. 499 - 512 (2020)
This study reports experimental data and kinetic modeling of acetic acid esterification with n-pentanol using sulfated zirconia as a catalyst. Reactions were carried out in an isothermal well-mixed batch reactor at different temperatures (50-80°C), n-pentanol to acid molar ratios (1:1-3:1), and catalyst loadings (5-10?wt% in relation to the total amount of acetic acid). The reaction mechanism regarding the heterogeneous catalysis was evaluated considering pseudo-homogeneous, Eley–Rideal, and Langmuir–Hinshelwood model approaches. The reaction mixture was considered a nonideal solution and the UNIQUAC thermodynamic model was used to take into account the nonidealities in the liquid phase. The results obtained indicated that increases in the temperature and catalyst loading increased the product formation, while changes in the n-pentanol to acetic acid molar ratio showed no significant effect. The estimated enthalpy of the reaction was ?8.49?kJ?mol?1, suggesting a slightly exothermic reaction. The Eley–Rideal model, with acetic acid adsorbed on the catalyst as the limiting step, was found to be the most significant reaction mechanism.
Molybdenum-modified mesoporous SiO2as an efficient Lewis acid catalyst for the acetylation of alcohols
Hlatshwayo, Xolani S.,Ndolomingo, Matumuene Joe,Bingwa, Ndzondelelo,Meijboom, Reinout
, p. 16468 - 16477 (2021/05/19)
A suitable, expeditious and well-organized approach for the acetylation of alcohols with acetic anhydride in the presence of 5%MoO3-SiO2 as an optimum environmentally benign heterogeneous catalyst was developed. The high surface area obtained for 5%MoO3-SiO2, 101 m2 g-1 compared to other catalysts, 22, 23, and 44 m2 g-1 for 5%WO3-ZrO2, 5%WO3-SiO2, and 5%MoO3-ZrO2, respectively, appears to be the driving force for better catalytic activity. Amongst the two dopants used, molybdenum oxide is the better dopant compared to its tungsten oxide counterpart. High yields of up to 86% were obtained with MoO3 doping while WO3 containing catalysts did not show any activity. Other reaction parameters such as reactor stirring speed, and solvent variation were studied and revealed that the optimum stirring speed is 400 rpm and cyclohexane is the best solvent. Thus, the utilization of affordable and nontoxic materials, short reaction times, reusability, and producibility of excellent yields of the desired products are the advantages of this procedure.
Synthesis and characterization of a new acid molten salt and the study of its thermal behavior and catalytic activity in Fischer esterification
Zaharani, Lia,Khaligh, Nader Ghaffari,Johan, Mohd Rafie,Gorjian, Hayedeh
, p. 7081 - 7088 (2021/05/03)
A new acid molten salt was prepared and its structure elucidation was conducted by FTIR, 1D NMR, 2D NMR, and mass spectrometry. Further support to elucidate the chemical structure of the 1H,4H-piperazine-N,N′-diium ring of the new acid molten salt was achieved by1H and13C NMR, and COSY analyses of 1H,4H-piperazine-N,N′-diium dibromide, which is synthesized and characterized for the first time in the current work. The analysis of FTIR and NMR spectra as well as pH and titrimetric analysis excluded the formation of [SO4]2?and the presence of an excess of H2SO4. Moreover, no distinguishing peak was detected for the acid proton of [HSO4]?in DMSO-d6. The thermal phase transition and thermal stability of the acid molten salt were also recorded, which approved the strong interaction between a dication and hydrogen sulfate anions. According to the acidity of the new molten salt, we encourage the study of its catalytic activity for the acetylation ofn-pentanol using glacial acetic acid. Pentyl acetate was obtained in 89.0% conversion and 78.0% isolated yield. The1H NMR spectrum of the residue showed an excess of HOAc together with molten salt, whereas the1H NMR spectrum of the upper phase exhibited pure pentyl acetate. After separation of the upper phase, the residue was concentrated and used in the next run without further purification. No significant changes in the chemical structure and catalytic activity of the new molten salt were observed even after the 5th run. Two chiral alcohols, including (?)-menthol and (+)-borneol, as well as α-tocopherol (α-TCP) were also acetylated with acetic acid in the presence of the new acid molten salt under optimized reaction conditions, which afforded the desired acetates in high yields.
Synthesis, Characterisation, and Determination of Physical Properties of New Two-Protonic Acid Ionic Liquid and its Catalytic Application in the Esterification
Shahnavaz, Zohreh,Zaharani, Lia,Khaligh, Nader Ghaffari,Mihankhah, Taraneh,Johan, Mohd Rafie
, p. 165 - 172 (2020/10/26)
A new ionic liquid was synthesised, and its chemical structure was elucidated by FT-IR, 1D NMR, 2D NMR, and mass analyses. Some physical properties, thermal behaviour, and thermal stability of this ionic liquid were investigated. The formation of a two-protonic acid salt namely 4,4′-trimethylene-N,N′-dipiperidinium sulfate instead of 4,4′-trimethylene-N,N′-dipiperidinium hydrogensulfate was evidenced by NMR analyses. The catalytic activity of this ionic liquid was demonstrated in the esterification reaction of n-butanol and glacial acetic acid under different conditions. The desired acetate was obtained in 62-88 % yield without using a Dean-Stark apparatus under optimal conditions of 10 mol-% of the ionic liquid, an alcohol to glacial acetic acid mole ratio of 1.3: 1.0, a temperature of 75-100°C, and a reaction time of 4 h. α-Tocopherol (α-TCP), a highly efficient form of vitamin E, was also treated with glacial acetic acid in the presence of the ionic liquid, and O-acetyl-α-tocopherol (Ac-TCP) was obtained in 88.4 % yield. The separation of esters was conducted during workup without the utilisation of high-cost column chromatography. The residue and ionic liquid were used in subsequent runs after the extraction of desired products. The ionic liquid exhibited high catalytic activity even after five runs with no significant change in its chemical structure and catalytic efficiency.
Alkyl substituted 4-N-oxazadisilinane cations: A new family of Si protic ionic liquids and its application on esterification reactions
Alhaddad, Maha,Chakraborty, Priyanka,Hu, Jinsong,Huang, Kuo-Wei
supporting information, (2020/06/08)
A series of oxazadisilinane compounds were prepared and used as Br?nsted bases to form a series of 21 siloxane protic ionic liquids (Si-PILs) with four different acids. This new family of Si-PILs were well characterized and examined to catalyze esterification reactions.
Porous supramolecular assemblies and functional properties of perhydroxylated cucurbit[6]uril and polyoxometallates
Xia, Xi,Ge, Wei Wei,Chen, Haiyong,Tao, Zhu,Zhang, Yunqian,Wei, Gang,Chen, Kai
, p. 10297 - 10304 (2019/07/08)
In the present work, perhydroxylated cucurbit[6]uril {(HO)12Q[6]} and Keggin-type polyoxometallates (POMs) such as H3[PMo12O40] and H3[PW12O40] were used as basic building blocks, and interaction of (HO)12Q[6] of POMs in the acidic aqueous solutions yielded two types of supramolecular assemblies. Hybrids of (HO)12Q[6] with POM anions were obtained from (HO)12Q[6]-POMs-HCl (1M) systems, whereas (HO)12Q[6]-based supramolecular assemblies without POMs were obtained from (HO)12Q[6]-POMs-HCl (6M) systems. The structures of these two assemblies were analyzed by using single X-ray single crystal and powder X-ray diffraction methods, and the chemical and physical properties of these two assemblies were investigated by using the multi-point Brunauer-Emmett-Teller (BET) method, the Barrett-Joyner-Halenda (BJH) method, UV/vis measurements and so on. The results revealed that the (HO)12Q[6]-POMs system may offer a feasible route for the uptake and release of POMs, exhibit esterification and aqueous dyes degradation catalytic activities, and adsorb volatile organic compounds, yielding adsorbing materials with interesting photochemical properties.
1,1,2,2-Tetrahydroperoxy-1,2-Diphenylethane: An efficient and high oxygen content oxidant in various oxidative reactions
Khosravi, Kaveh,Naserifar, Shirin
supporting information, p. 6584 - 6592 (2018/10/05)
Several oxidative approaches namely thiocyanation of aromatic compounds, epoxidation of alkenes, amidation of aromatic aldehydes, epoxidation of α β-unsaturated ketones, oxidation of sulfides to sulfoxides and sulfones, bayer-villeger reaction, bromination and iodation of aniline and phenol derivatives oxidative esterification, oxidation of pyridines and oxidation of secondary, allylic and benzyllic alcohols were carried out using 1,1,2,2-Tetrahydroperoxy-1,2-Diphenylethane as the potential solid oxidant which can be stored for several months without any loss in its activity. All of the procedures were accomplished via mild reaction conditions and the products were afforded in high yields and short reaction times.
Ester Synthesis in Water: Mycobacterium smegmatis Acyl Transferase for Kinetic Resolutions
de Leeuw, Nicolas,Torrelo, Guzman,Bisterfeld, Carolin,Resch, Verena,Mestrom, Luuk,Straulino, Emanuele,van der Weel, Laura,Hanefeld, Ulf
, p. 242 - 249 (2017/11/16)
The acyl transferase from Mycobacterium smegmatis (MsAcT) catalyses transesterification reactions in aqueous media because of its hydrophobic active site. Aliphatic cyanohydrin and alkyne esters can be synthesised in water with excellent and strikingly opposite enantioselectivity [(R);E>37 and (S);E>100, respectively]. When using this enzyme, the undesired hydrolysis of the acyl donor is an important factor to take into account. Finally, the choice of acyl donor can significantly influence the obtained enantiomeric excesses. (Figure presented.).
Selective Hydrogenolysis of Furfural Derivative 2-Methyltetrahydrofuran into Pentanediol Acetate and Pentanol Acetate over Pd/C and Sc(OTf)3 Cocatalytic System
Zhang, Kun,Li, Xing-Long,Chen, Shi-Yan,Xu, Hua-Jian,Deng, Jin,Fu, Yao
, p. 726 - 734 (2018/02/06)
It is of great significance to convert platform molecules and their derivatives into high value-added alcohols, which have multitudinous applications. This study concerns systematic conversion of 2-methyltetrahydrofuran (MTHF), which is obtained from furfural, into 1-pentanol acetate (PA) and 1,4-pentanediol acetate (PDA). Reaction parameters, such as the Lewis acid species, reaction temperature, and hydrogen pressure, were investigated in detail. 1H NMR spectroscopy and reaction dynamics study were also conducted to help clarify the reaction mechanism. Results suggested that cleavage of the primary alcohol acetate was less facile than that of the secondary alcohol acetate, with the main product being PA. A PA yield of 91.8 % (150 °C, 3 MPa H2, 30 min) was achieved by using Pd/C and Sc(OTf)3 as a cocatalytic system and an 82 % yield of PDA was achieved (150 °C, 30 min) by using Sc(OTf)3 catalyst. Simultaneously, the efficient conversion of acetic esters into alcohols by simple saponification was carried out and led to a good yield.
