- Functionalized dicationic ionic liquids: Green and efficient alternatives for catalysts in phthalate plasticizers preparation
-
Two highly acidic, imidazolium-based, functionalized dicationic ionic liquids (FDCILs) were synthesized and characterized by FTIR, 1H NMR and13C NMR. The synthesized FDCILs were used as efficient and green catalysts in the synthesis of phthalate plasticizers through esterification of phthalic anhydride (PhA) with ethanol, n-propanol and n-butanol. Among these two FDCILs, (dimethyl-4-sulfobutyl-ammonium) 1,2-ethan-1-methyl-imidazolium-sulfonic acid hydrogen sulfate performed better. The catalytic activity of FDCIL is related to the density of acidic groups on it and the length of the carbon chain in the cationic part. The influences of the reaction temperature, catalyst dosage, and molar ratio of phthalic anhydride to alcohol on the esterification reaction were investigated. The reusability of the catalyst in these reactions was studied too. The diester phthalates were obtained up to 98.8% yield. The products can be separated easily by decantation from the reaction mixture. [Figure not available: see fulltext.]
- Zekri, Negar,Fareghi-Alamdari, Reza,Khodarahmi, Zahra
-
-
Read Online
- Diacidic ionic liquid supported on magnetic-silica nanocomposite: a novel, stable, and reusable catalyst for selective diester production
-
Abstract: Supported diacidic ionic liquid on magnetic silica nanoparticles (SDAIL@magnetic nanoSiO2) was successfully prepared through a multi-step approach. 2,2- bis ((3- methylimidazolidin-1-yl) methyl) propane- 1,3- diol bromide salt was immobilized onto the surface of magnetic silica nanoparticles via covalent bonding to prepare a novel powerful acidic catalyst. The synthesized catalyst was characterized by FT-IR, SEM, TGA, VSM, N2 adsorption–desorption measurements and acid-base titration. The catalytic activity of the prepared SDAIL@magnetic nanoSiO2 was investigated for the selective diesterification of alcohols by phthalic anhydride to afford corresponding dialkyl plasticizers under solvent-free conditions. The nature of two acidic counter anions as well as the presence of Lewis acidic species (Fe3O4) on the magnetic nanosilica and high surface area of the nanosilica influenced the behavior of the catalyst. Surperisingly, the high acidic character of the catalyst facilitates the reaction with a short reaction time. Furthermore, TG analysis strongly demonstrates that major content of IL is still stable on the support up to 290?°C, so catalyst has a good thermal stability. Under the optimized conditions, the conversion of phthalic anhydride was 100% and diester plasticizers were obtained with excellent yields (80–100%). The SDAIL@magnetic nanoSiO2 catalyst showed a good reusability and could be easily separated from the reaction mixture using an external magnet thanks to its superparamagnetic behavior and reused for several runs without significant activity loss. An important advantage of the SDAIL@magnetic nanoSiO2 was its high-hydrophilicity resulted in excellent selectivity towards the formation of only diesters which are commonly used plasticizers in different industries. Graphical abstract [Figure not available: see fulltext.].
- Fareghi-Alamdari, Reza,Nadiri Niri, Mehri,Hazarkhani, Hassan,Zekri, Negar
-
p. 2615 - 2629
(2018/09/13)
-
- A novel hydrogen-bonded silica-supported acidic ionic liquid: An efficient, recyclable and selective heterogeneous catalyst for the synthesis of diesters
-
Abstract: In this study, two novel acidic ionic liquids, including a hydroxyl functionalized diacidic ionic liquid [HFDAIL] and a sulfonated diacidic ionic liquid [SFDAIL], were prepared and immobilized on the surface of silica nanoparticles (SNPs) via hydrogen bonding. The materials were characterized by FT-IR, NMR, SEM, nitrogen physisorption measurement, TGA and acid-base titration. The catalytic activity of the prepared catalysts was investigated in the synthesis of phthalate, maleate and succinate diesters under solvent-free conditions. It was found that nanosilica@[HFDAIL] with higher availability of acidic sites and higher hydrophilicity was more efficient compared to the nanosilica@[SFDAIL]. Notably, nanosilica@[HFDAIL] catalyst has also demonstrated excellent selectivity for the diester product while the monoester product was predominant in the case of nanosilica@[SFDAIL] even after prolonged reaction time or higher catalyst loading. In addition, the nanosilica@[HFDAIL] catalyst could be separated by simple filtration and reused several times without any significant loss of catalytic performance, but a remarkable decrease in activity was observed for nanosilica@[SFDAIL] in the next runs. GRAPHICAL ABSTRACT?: SYNOPSIS Two novel acidic ionic liquids, including a hydroxyl functionalized diacidic ionic liquid [HFDAIL] and a sulfonated diacidic ionic liquid [SFDAIL], were prepared and immobilized on the surface of silica nanoparticles via hydrogen bonding. The catalytic activity of the catalysts was investigated in the synthesis of diesters under solvent-free conditions.
- Fareghi-Alamdari, Reza,Niri, Mehri Nadiri,Hazarkhani, Hassan
-
-
- Synthesis and characterization of a new hydroxyl functionalized diacidic ionic liquid as catalyst for the preparation of diester plasticizers
-
Two new functionalized diacidic ionic liquids (FDAILs) including hydroxyl functionalized diacidic ionic liquid (HFDAIL) and sulfonated diacidic ionic liquid (SFDAIL) were synthesized and characterized by 1HNMR, 13CNMR and FT-IR. The catalytic activities of these FDAILs were examined in esterification reaction of anhydrides with some alcohols to give corresponding dialkyl plasticizers under solvent-free conditions. The results indicate that HFDAIL, as hydroxyl-bearing catalyst, show better catalytic performance. Under the optimum conditions, using HFDAIL, the conversion of phthalic anhydride was high and diester plasticizers were obtained with good to excellent yields in the presence of only 10?mol% of ionic liquid. All the produced diesters could be easily recovered due to their immiscibility with the ionic liquid. Recycling experiments suggests that these ionic liquids can be reused several times without remarkable loss in their catalytic activity.
- Fareghi-Alamdari, Reza,Nadiri Niri, Mehri,Hazarkhani, Hassan
-
p. 153 - 160
(2016/12/30)
-
- Facile esterification of carboxylic acid using amide functionalized benzimidazolium dicationic ionic liquids
-
Herein, we report the synthesis of a new series of amide functionalized dicationic benzimidazolium based ionic liquids (DBimILs) and appraised their efficacy towards perceptive esterification of carboxylic acids with alkyl/allyl/aryl halides in presence of triethylamine. The amide groups present in this new series of DBimILs are expected to form hydrogen bonding with the carboxylic acids and this could facilitate the esterification reactions under mild conditions devoid of any added catalyst or organic solvent. The plausible mechanism for the enhanced catalytic activity in presence of this new series of ILs has been proposed. The corresponding alkyl/allyl/aryl esters isolated from this reaction were of high purity after simple extraction, which wipe out the necessity for further purification. This protocol addresses clean methodology and the efficient recyclability as well as reusability of the catalyst.
- Muskawar, Prashant Narayan,Thenmozhi,Gajbhiye, Jayant M.,Bhagat, Pundlik Rambhau
-
p. 214 - 220
(2014/07/08)
-
- METHOD FOR CONTINUOUSLY PREPARING CARBOXYLIC ACID ESTER
-
A method for continuously preparing a carboxylic acid ester is disclosed. In the method of the present invention, a vertical reactor is filled with a solid catalyst, a carboxylic acid and an alcohol are introduced into a lower part of the vertical reactor, esterification is performed to form an esterized mixture, the esterized mixture is output from an upper part of the vertical reactor, and distillation is performed to isolate the carboxylic acid ester. The method of the present invention is simple, easily controlled and environmental friendly, and has significantly high conversion rate and selectivity.
- -
-
Paragraph 0034
(2013/11/19)
-
- Synthesis, characterization and catalytic properties of SAPO-11, -31 and -41 molecular sieves
-
Medium pore molecular sieves, SAPO-11, SAPO-31 and SAPO-41, have been synthesized using di-n-propylamine and diethylamine as the organic template. They have been characterized by various methods such as elemental analysis, X-ray powder diffraction, solid state MAS NMR spectroscopy, and FT-IR spectroscopy in the framework and hydroxyl regions. Catalytic activities of these materials in the esterification of phthalic anhydride with different alcohols have been studied. The catalytic activity of these material is in the order: SAPO-41> SAPO-11> SAPO-31.
- Venkatathri,Srivastava
-
p. 1039 - 1043
(2007/10/03)
-
- Fe2(SO4)3·xH2O in synthesis: A convenient and efficient catalyst for the esterification of aromatic carboxylic acids with alcohols
-
Fe2(SO4)3·xH2O has been used for the catalyst in the esterification of aromatic carboxylic acids with alcohols. The method offers mild reaction condition, easy work-up, and high yields of the esterification products.
- Zhang, Gui-Sheng
-
p. 607 - 611
(2007/10/03)
-
- ALKYLATING PROPERTIES OF ALKYL PHOSPHITEDIETHYL AZODICARBOXYLATE REAGENT
-
Reaction of caoxylic acids, phenols, and some imides with phosphite esters in presence of diethyl azodicarboxylate result in transfer of an alkyl group from phosphite to a protic acid molecule In the case of enolizable C-H acids selective formation of O-alkylated products was observed.The reactions proceed under mild, virtually neutral conditions, affording good yields of alkylated products.
- Grynkiewicz, Grzegorz
-
p. 149 - 152
(2007/10/02)
-
