Chemical Fixation Of Carbon Dioxide Research Articles

Poly(4‐vinylimidazolium)s/Diazabicyclo[5.4.0]undec‐7‐ene/Zinc(II) Bromide‐Catalyzed Cycloaddition of Carbon Dioxide to Epoxides

AbstractPoly(4‐vinylimidazolium)s, derived from the self‐immobilization of 4‐vinylimidazoliums, with diazabicyclo[5.4.0]undec‐7‐ene (DBU) and zinc bromide (ZnBr2) are used as a highly efficient catalyst for the chemical fixation of carbon dioxide. This catalytic system has been applied for the preparation of cyclic carbonates from terminal epoxides and carbon dioxide. Many functional groups, including chloro, vinyl, ether, and hydroxy groups are well tolerated in the reactions. Moreover, the catalytic system was found to catalyze the conversion of more sterically congested epoxides which are generally considered to be challenging substrates for fabricating the cyclic organic carbonates. In addition, the disubstituted epoxides are found to react with retention of configuration. The polymer precatalyst is easily recovered and reused. A plausible reaction mechanism is proposed.magnified image

Recent progress in catalytic conversions of carbon dioxide

Chemical fixation of carbon dioxide (CO2), which is an inexpensive and renewable carbon source, is becoming more and more important. The development of both new reactions and new catalysts is needed to overcome the kinetic and thermodynamic stability of CO2. Organic and metal catalysts with unique and excellent activity and selectivity have been developed for various chemical conversions of CO2. In this perspective, we provide an overview of the recent progress in this field, classifying it into several categories, where each research is concisely summarized one by one using a single reaction scheme, a representative catalyst structure, and/or a catalytic cycle.

Superbase/cellulose: an environmentally benign catalyst for chemical fixation of carbon dioxide into cyclic carbonates

An environmentally benign catalytic system consisting of 1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) and cellulose was developed for CO2 chemical fixation with epoxides under metal-free and halide-free conditions. Due to the dual roles played by DBU and cellulose on the activations of CO2 and epoxide, the reaction could be performed with high activity and selectivity. A possible catalytic cycle for the hydrogen bond assisted ring-opening of epoxide and the activation of CO2 induced by DBU was proposed. The process herein represents a simple, ecologically safe and efficient route for CO2 chemical fixation into high value chemicals.

Insights on recyclable catalytic system composed of task-specific ionic liquids for the chemical fixation of carbon dioxide

Several imidazolium ionic liquids display high efficiency as catalysts for the sequential oxidation of alkene and carboxylation of epoxide.

Magnetic base catalysts for the chemical fixation of carbon dioxide to quinazoline-2,4(1H,3H)-diones

TBD-functionalized Fe3O4 was proven to be an efficient and recyclable magnetic heterogeneous catalyst for the chemical fixation of CO2 with 2-aminobenzonitriles under mild conditions.

Amino acid/KI as multi-functional synergistic catalysts for cyclic carbonate synthesis from CO2under mild reaction conditions: a DFT corroborated study

Naturally occurring amino acids were identified as efficient co-catalysts for the alkali metal halide-mediated synthesis of cyclic carbonates from carbon dioxide and epoxides under mild, solvent free reaction conditions. The binary system of histidine/potassium iodide gave an appreciable turnover number of 535 for propylene oxide in 3 h. Detailed studies evaluating a variety of amino acids revealed that the basic amino acids afforded better conversion rates. The formation of a seven membered ring involving the zwitterionic ends of the amino acid, the metal halide, and the epoxide was considered to accelerate the catalysis rate. Density functional theory calculations were performed for the first time on amino acid co-catalyzed cycloaddition to provide further evidence for this hypothesis. The iodide ions of the alkali metal halide displayed excellent synergism with the hydrogen bonding groups of the amino acids in the production of cyclic carbonates, whereas bromide and chloride anions functioned less efficiently. The utilization of amino acids to enhance the catalytic activity of the cheap and eco-friendly alkali metal halides for cyclic carbonate synthesis represents a cost-effective, greener route towards the chemical fixation of carbon dioxide.

Theoretical study on the chemical fixation of carbon dioxide with propylene oxide catalyzed by ammonium and guanidinium salts

The cycloaddition of carbon dioxide onto propylene oxide catalysed by ammonium and guanidinium salts has been investigated using density functional theory (DFT) in order to understand the catalytic mechanism and the role of the cation and the anion. Two different possible pathways were considered, but it has been found that the one whereby the activation of the epoxide by the onium salt occurs before the addition of CO2 was consistent with the experimental findings. The rate-determining step was found to be the ring opening of the epoxide that results from the nucleophilic attack of the anion of the catalyst on the non-substituted carbon of the epoxide ring. Moreover, we found that in order to have an efficient catalyst, it is necessary to have an anion with an ambivalent nature (a high nucleophilicity and good leaving group ability). Finally, it turns out that for a given anion, the guanidinium salt is more efficient than the ammonium salt in opening the epoxide ring, thanks to the ability of the guanidinium cation to form hydrogen bonds with the oxygen of the epoxide.

Scope of chemical fixation of carbon dioxide catalyzed by a bifunctional monomeric tungstate

The tungsten-oxo moiety in a simple monomeric tungstate, TBA2[WO4] (I, TBA=tetra-n-butylammonium), showed bifunctional activation of both CO2 and 1,2-phenylenediamine (1a). It was confirmed by 1H, 13C, and 183W NMR spectroscopies that adducts I–1a and I–(CO2)n (n=1 and 2) were formed by the reactions of I with 1a and CO2, respectively. These adducts played important roles in formation of the corresponding carbamic acid intermediates. The present bifunctionality could be applied to chemical fixation of CO2 even at atmospheric pressure with various kinds of structurally diverse aryl diamines, primary monoamines, propargylic alcohols, and propargylic amines into cyclic urea derivatives, 1,3-disubstituted urea derivatives, cyclic carbonates, and cyclic carbamates, respectively.

Gold, palladium and gold–palladium supported nanoparticles for the synthesis of glycerol carbonate from glycerol and urea

Supported Au–Pd nanoparticles are shown to be effective catalysts for the transformation of glycerol into glycerol carbonate. The reaction of glycerol with urea to form glycerol carbonate is a very attractive reaction that utilises two inexpensive and readily available raw materials in a chemical cycle that, overall, results in the chemical fixation of carbon dioxide. Previous reports are largely based on the utilisation of high concentrations of metal sulphates or oxides, which suffer from low intrinsic activity and selectivity and limited recoverability due to the dissolution of the catalyst in the reaction media. We now report that magnesium oxide is an excellent support for gold and bimetallic gold–palladium nanoparticles for this reaction. The preparation method and pre-treatment affect the catalytic performance and a colloidal preparation route produces the most active catalysts.

Is CO2 fixation promoted through the formation of DBU bicarbonate salt?

AbstractThe bicyclic amidines, 1,8‐diazabicyclo [5.4.0]undec‐7‐ene (DBU) and 1,5‐diazabicyclo[4.3.0] non‐5‐ene (DBN), were used for the chemical fixation of carbon dioxide. The promotion for CO2 fixation is often reported through the formation of a thermally unstable DBU or DBN bicarbonate salt. To examine the effects of the DBU or DBN bicarbonate salt, reactions of 2‐aminobenzonitrile with the DBU salt or DBN salt in dimethylformamide (DMF) were performed at 20°C for 24 h in argon or carbon dioxide (0.1 MPa). However, in all the cases, 1H‐quinazoline‐2,4‐dione was not obtained completely. In contrast with room temperature reactions, 2‐aminobenzonitriles and DBU bicarbonate salt in DMF reacted for 4 h under high temperature (80°C) and CO2 atmosphere (0.1 MPa) gave 1H‐quinazoline‐2,4‐diones in good to excellent yields. At high‐temperature conditions, DBU bicarbonate salt is decomposed to DBU and carbon dioxide. Also, the carbonylation of 2‐aminobenzonitrile using DBU and carbon dioxide afforded 1H‐quinazoline‐2,4‐dione in good yields under similar reaction conditions. These results suggest that the combination of DBU or DBN as a strong base and carbon dioxide is much more important than the in situ formation of DBU or DBN bicarbonate salt for the acceleration of CO2 fixation. © 2012 Wiley Periodicals, Inc. Heteroatom Chem 23:276–280, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/hc.21014

Multilayered Supported Ionic Liquids as Catalysts for Chemical Fixation of Carbon Dioxide: A High‐Throughput Study in Supercritical Conditions

Multilayered, covalently supported ionic liquid phase (mlc-SILP) materials were synthesized by using a new approach based on the grafting of bis-vinylimidazolium salts on different types of silica or polymeric supports. The obtained materials were characterized and tested as catalysts in the reaction of supercritical carbon dioxide with various epoxides to produce cyclic carbonates. The material prepared by supporting a bromide bis-imidazolium salt on the ordered mesoporous silica SBA-15 was identified as the most active catalyst for the synthesis of cyclic carbonates and displayed improved productivity compared with known supported ionic liquid catalysts. The catalyst retained its high activity upon reuse in consecutive catalytic runs. This is the first report of the application of mlc-SILP materials as catalysts in a reaction for the fixation of carbon dioxide. Rapid, parallel screening and comparison of the catalysts was performed by means of high-throughput experimentation.

A computational study on the chemical fixation of carbon dioxide with 2-aminobenzonitrile catalyzed by 1-butyl-3-methyl imidazolium hydroxide ionic liquids

The mechanism of chemical fixation of carbon dioxide with 2-aminobenzonitrile catalyzed by 1-butyl-3-methyl imidazolium hydroxide ([Bmim]OH) ionic liquid has been extensively investigated by the density functional theory (DFT) calculations. The purpose is to show the detailed reaction mechanism, and in particular to better understand the role of [Bmim]OH played in the reaction as a catalyst. Three mechanistic pathways are proposed and evaluated. Our calculations indicate that the real activate catalyst is the N-heterocyclic carbine (NHC). In the favored pathway, it is found that the attack of C3 atom of NHC to C1 atom, the C1–O2 bond cleavage, and the C1–N2 bond formation have close activation free energies. Therefore, each of them can determine the reaction rate with variation in the reaction conditions. Furthermore, it is shown that the scCO 2 solution does not change significantly the potential energy surface profile.

Brønsted Acidic Ionic Liquids Mediated Metallic Salts Catalytic System for the Chemical Fixation of Carbon Dioxide to Form Cyclic Carbonates

The catalysts of COOH- and SO3H-functionalized ionic liquids mediated metallic salts had been developed for the coupling of carbon dioxide and epoxides to form cyclic carbonates under mild reaction conditions without using additional organic solvents. The effects of different ionic liquids, metallic salts, varying the molar ratio of ionic liquid to metallic salt and reaction conditions were examined. The excellent yield of cyclic carbonates and the high turnover frequencies (TOF) were obtained at the optimum reaction conditions. In addition, the catalytic system offered high stability and reusability. The catalysts of Bronsted acidic ionic liquids mediated metallic salts had been developed for the coupling of carbon dioxide and epoxides to form cyclic carbonates with significant catalytic activity under mild reaction conditions. Additional, this catalyst system also offers the advantages of recyclability and reusability.

ChemInform Abstract: N‐Heterocyclic Carbene Functionalized MCM‐41 as an Efficient Catalyst for Chemical Fixation of Carbon Dioxide.

AbstractThe title catalyst shows temperature dependent and reversible binding of carbon dioxide.

Efficient catalyst-free chemical fixation of carbon dioxide into 2-oxazolidinones under supercritical condition

Abstract 4-Methylene-1,3-oxazolidin-2-ones can be synthesized from propargylic alcohols, primary amines and carbon dioxide under supercritical condition in the absence of any additional catalyst and solvent. Various propargylic alcohols and primary amines were examined.

Highly efficient chemical fixation of carbon dioxide catalyzed by high-valent tetraphenylporphyrinatotin(IV) triflate

Abstract High-valent tetraphenylporphyrinatotin(IV) triflate, [Sn IV (TPP)(OTf) 2 ], was found as an efficient catalyst for the coupling of several epoxides (linear and cyclic) with carbon dioxide in the presence of tetrabutylphosphonium bromide as co-catalyst at atmospheric pressure. The reaction temperature, kind of solvent, co-catalyst and axial ligand effect were also investigated.

Electron-deficient tin(IV)tetraphenylporphyrin perchlorate: A highly efficient catalyst for chemical fixation of carbon dioxide

Electron-deficient tin(IV)tetraphenylporphyrin perchlorate, [Sn IV(TPP)(ClO 4) 2] was used as a highly efficient catalyst for chemical fixation of carbon dioxide. The bifunctional catalytic system [Sn(TPP)(ClO 4) 2]/tetrabutylphosphonium bromide (TBPB) was applied for preparation of cyclic carbonates from epoxides and carbon dioxide. The effect of reaction parameters was also investigated.

A Computational Study on the Chemical Fixation of Carbon Dioxide with Epoxide Catalyzed by LiBr Salt

The chemical fixation of carbon dioxide with 2,3-epoxypropyl phenyl ether catalyzed by LiBr salt to produce a five-membered cyclic carbonate, 4-(phenoxymethyl)-1,3-dioxolan-2-one, has been extensively investigated at the B3LYP density functional level of theory. The solvent effects have been studied by means of a PCM model. All possible pathways are examined, and their corresponding energetics are demonstrated. Our results reveal that the overall reaction comprises three main steps: epoxide ring-opening, carbon dioxide insertion, and ring-closure of cyclic carbonate, none of which contains significantly large barriers. On the basis of the computed free energies of activation, the rate-determining step can be the ring-opening of epoxide or the ring-closure of cyclic carbonate with variation in the reaction conditions in N-methylpyrrolidinone (NMP) solvent. Our calculations indicate that path 2 is more favorable than path 1 in the gas phase, while both of them exist possibly in NMP solvent. The overall reaction is exothermic. Furthermore, the free energy profiles of all reaction pathways along the minima energy path in the gas phase and in NMP solvent were obtained and compared. It is shown that NMP solvent does not change the general trends for the reaction potential energy surfaces.

N-Heterocyclic carbene functionalized MCM-41 as an efficient catalyst for chemical fixation of carbon dioxide

N-Heterocyclic carbene (NHC) functionalized MCM-41 was synthesized by reacting 1,3-bis-(4-allyl-2,6-diisopropylphenyl) imidazolium chloride with MCM-41 using 3-mercaptopropyltrimethoxysilane as silane coupling agent, and its CO2 adduct (designated as MCM-41-IPr-CO2) was further synthesized by the reaction with CO2. In situdiffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) was used to investigate the reversible CO2 capture-release ability of MCM-41-NHC. MCM-41-IPr-CO2 adduct proved to be an efficient heterogeneous catalyst for the cycloaddition of CO2 to epoxides or aziridines with excellent regioselectivity under mild conditions. Moreover, the catalyst could be recovered easily through a simple filtration process and reused multiple times without obvious loss in activity, owing to CO2 as protective group for effectively stabilizing the NHC anchored on MCM-41.

ChemInform Abstract: Polystyrene‐Supported Amino Acids as Efficient Catalyst for Chemical Fixation of Carbon Dioxide.

AbstractDioxolanones and oxazolidinones are prepared by treatment of epoxides or aziridines, respectively, with CO2 under neat conditions in the presence of only 0.6 mol% of polymer‐supported threonine or tyrosine.