Special Issue "Catalysis in Innovative Solvents"

A special issue of Catalysts (ISSN 2073-4344).

Deadline for manuscript submissions: closed (30 June 2017)

Special Issue Editors

Guest Editor
Prof. Dr. Montserrat Gómez

Université de Toulouse 3 - Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée, UMR CNRS 5069, 118, route de Narbonne, 31062 Toulouse cedex 9, France
Website | E-Mail
Interests: design of metal-based catalysts; heteropolymetallic complexes, mono- and bimetallic nanoparticles; innovative solvents (ionic liquids, glycerol); nanocatalysis; surface reactivity; one-pot multi-step processes.
Guest Editor
Dr. Daniel Pla

Université de Toulouse 3 - Paul Sabatier, Laboratoire Hétérochimie Fondamentale et Appliquée, UMR CNRS 5069, 118, route de Narbonne, 31062 Toulouse cedex 9, France
Website | E-Mail
Interests: development of novel chemical methodologies based on hetero-annulation strategies; natural product synthesis; transition metal-catalyzed C–H bond activation and cross coupling reactions; nanocatalysis.

Special Issue Information

Dear Colleagues,

The use of non-conventional solvents in catalysis enables the pursuit of unique challenges towards the design and implementation of environmentally friendly, sustainably efficient, and robust synthetic methodologies for the future. The advantages in terms of catalyst recycling, re-usage of the catalytic phase, and product separation validate the potential of technology transfer that this field has to offer. In this Special Issue, we aim at showcasing the latest advances in different types of media, such as ionic liquids and deep eutectic solvents (DES), supercritical CO2, fluorinated solvents, glycols (polyethylene glycol, glycerol), or even water and biphasic systems applied to catalysis, including supported liquid catalytic phases (e.g., inorganic oxides, carbon-based materials, etc.).

This Special Issue focuses on recent works of catalysed processes carried out in innovative media including: a) metal-based catalysis (complexes, nanoparticles), organocatalysis and biocatalysis; b) mechanistic studies; and c) applications in (total) syntheses.

Dr. Daniel Pla
Prof. Dr. Montserrat Gómez
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Catalysts is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Published Papers (8 papers)

View options order results:
result details:
Displaying articles 1-8
Export citation of selected articles as:

Research

Jump to: Review

Open AccessFeature PaperCommunication Halide-Enhanced Catalytic Activity of Palladium Nanoparticles Comes at the Expense of Catalyst Recovery
Catalysts 2017, 7(9), 280; doi:10.3390/catal7090280
Received: 24 July 2017 / Revised: 7 September 2017 / Accepted: 13 September 2017 / Published: 19 September 2017
PDF Full-text (2756 KB) | HTML Full-text | XML Full-text
Abstract
In this communication, we present studies of the oxidative homocoupling of arylboronic acids catalyzed by immobilised palladium nanoparticles in aqueous solution. This reaction is of significant interest because it shares a key transmetallation step with the well-known Suzuki-Miyaura cross-coupling reaction. Additives can have
[...] Read more.
In this communication, we present studies of the oxidative homocoupling of arylboronic acids catalyzed by immobilised palladium nanoparticles in aqueous solution. This reaction is of significant interest because it shares a key transmetallation step with the well-known Suzuki-Miyaura cross-coupling reaction. Additives can have significant effects on catalysis, both in terms of reaction mechanism and recovery of catalytic species, and our aim was to study the effect of added halides on catalytic efficiency and catalyst recovery. Using kinetic studies, we have shown that added halides (added as NaCl and NaBr) can increase the catalytic activity of the palladium nanoparticles more than 10-fold, allowing reactions to be completed in less than half a day at 30 °C. However, this increased activity comes at the expense of catalyst recovery. The results are in agreement with a reaction mechanism in which, under conditions involving high concentrations of chloride or bromide, palladium leaching plays an important role. Considering the evidence for analogous reactions occurring on the surface of palladium nanoparticles under different reaction conditions, we conclude that additives can exert a significant effect on the mechanism of reactions catalyzed by nanoparticles, including switching from a surface reaction to a solution reaction. The possibility of this switch in mechanism may also be the cause for the disagreement on this topic in the literature. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Figure 1

Open AccessFeature PaperArticle Catalytic Performance of Fe(II)-Scorpionate Complexes towards Cyclohexane Oxidation in Organic, Ionic Liquid and/or Supercritical CO2 Media: A Comparative Study
Catalysts 2017, 7(8), 230; doi:10.3390/catal7080230
Received: 27 June 2017 / Revised: 23 July 2017 / Accepted: 26 July 2017 / Published: 2 August 2017
PDF Full-text (1135 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
The catalytic activity of the iron(II) C-scorpionate complexes [FeCl2{HC(pz)3}] 1 (pz = pyrazol-1-yl) and [FeCl2{HOCH2C(pz)3}] 2, and of their precursor FeCl2·2H2O 3, towards cyclohexane oxidation with tert
[...] Read more.
The catalytic activity of the iron(II) C-scorpionate complexes [FeCl2{HC(pz)3}] 1 (pz = pyrazol-1-yl) and [FeCl2{HOCH2C(pz)3}] 2, and of their precursor FeCl2·2H2O 3, towards cyclohexane oxidation with tert-butyl hydroperoxide was evaluated and compared in different media: acetonitrile, ionic liquids (1-butyl-3-methylimidazolium hexafluorophosphate, [bmim][PF6], and 1-butyl-3-methylimidazolium tris(pentafluoroethyl)trifluorophosphate, [bmim][FAP]), supercritical carbon dioxide (scCO2), and scCO2/[bmim][X] (X = PF6 or FAP) mixtures. The use of such alternative solvents led to efficient and selective protocols for the oxidation of cyclohexane. Moreover, tuning the alcohol/ketone selectivity was possible by choosing the suitable solvent. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Open AccessFeature PaperArticle Solventless Coupling of Epoxides and CO2 in Compressed Medium Catalysed by Fluorinated Metalloporphyrins
Catalysts 2017, 7(7), 210; doi:10.3390/catal7070210
Received: 22 June 2017 / Revised: 22 June 2017 / Accepted: 7 July 2017 / Published: 14 July 2017
PDF Full-text (2161 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Metal complexes of meso-arylporphyrins (Cr(III), Fe(III), and Zn(II)) were evaluated in the coupling reaction of cyclohexene oxide (CHO) with CO2 in compressed medium, where the Cr complexes were demonstrated to be the most active systems, leading predominantly to copolymerisation products. It
[...] Read more.
Metal complexes of meso-arylporphyrins (Cr(III), Fe(III), and Zn(II)) were evaluated in the coupling reaction of cyclohexene oxide (CHO) with CO2 in compressed medium, where the Cr complexes were demonstrated to be the most active systems, leading predominantly to copolymerisation products. It is noteworthy that no addition of solvent was required. To improve the catalytic activity, and to simultaneously increase the solubility in compressed CO2, a new fluorinated catalyst, tetrakis(4-trifluoromethylphenyl)porphyrinatochromium(III) chloride (CrCl-pCF3TPP), was applied to this reaction. The alternating copolymerisation of CHO with CO2, using the Cr(III) fluorinated porphyrin catalyst, required the use of a co-catalyst, bis(triphenylphosphine)iminium chloride (PPNCl), with the best yields of copolymers being obtained at 80 °C, and CO2 pressures in the range of 50–110 bar, over a period of 24 h, with a low catalyst/substrate molar ratio (0.07%). The polycarbonate’s structure was analysed by 1H NMR, 13C NMR, and MALDI-TOF spectroscopy, which demonstrated high carbonate incorporations (98–99%). Gel permeation chromatography revealed number-average molecular weights (Mn) in the range of 4800–12,800 and narrow molecular weight distributions (Mw/Mn ≤ 1.63). Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Figure 1

Open AccessArticle A Reusable Palladium/Cationic 2,2′-Bipyridyl System-Catalyzed Double Mizoroki-Heck Reaction in Water
Catalysts 2017, 7(6), 177; doi:10.3390/catal7060177
Received: 2 May 2017 / Revised: 27 May 2017 / Accepted: 31 May 2017 / Published: 2 June 2017
PDF Full-text (14348 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
A reusable PdCl2(NH3)2/cationic 2,2′-bipyridyl system was used to catalyze the double Mizoroki-Heck reaction of aryl iodides with electron-deficient alkenes in water in the absence of inert gas, giving β,β-diarylated carbonyl derivatives in good to excellent yields. The
[...] Read more.
A reusable PdCl2(NH3)2/cationic 2,2′-bipyridyl system was used to catalyze the double Mizoroki-Heck reaction of aryl iodides with electron-deficient alkenes in water in the absence of inert gas, giving β,β-diarylated carbonyl derivatives in good to excellent yields. The formation of unsymmetrical β,β-diarylated alkenes were also studied by coupling aryl iodides with the corresponding aryl-substituted α,β-unsaturated carbonyl compounds. This water-soluble catalyst can be swiftly separated from the organic layer using simple extraction for the further reuse, and, thus, makes it an operationally-simple and environmentally-benign procedure. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Open AccessArticle Are Directed Evolution Approaches Efficient in Exploring Nature’s Potential to Stabilize a Lipase in Organic Cosolvents?
Catalysts 2017, 7(5), 142; doi:10.3390/catal7050142
Received: 27 March 2017 / Revised: 2 May 2017 / Accepted: 3 May 2017 / Published: 7 May 2017
Cited by 1 | PDF Full-text (4137 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Despite the significant advances in the field of protein engineering, general design principles to improve organic cosolvent resistance of enzymes still remain undiscovered. Previous studies drew conclusions to engineer enzymes for their use in water-miscible organic solvents based on few amino acid substitutions.
[...] Read more.
Despite the significant advances in the field of protein engineering, general design principles to improve organic cosolvent resistance of enzymes still remain undiscovered. Previous studies drew conclusions to engineer enzymes for their use in water-miscible organic solvents based on few amino acid substitutions. In this study, we conduct a comparison of a Bacillus subtilis lipase A (BSLA) library—covering the full natural diversity of single amino acid substitutions at all 181 positions of BSLA—with three state of the art random mutagenesis methods: error-prone PCR (epPCR) with low and high mutagenesis frequency (epPCR-low and high) as well as a transversion-enriched Sequence Saturation Mutagenesis (SeSaM-Tv P/P) method. Libraries were searched for amino acid substitutions that increase the enzyme’s resistance to the water-miscible organic cosolvents 1,4-dioxane (DOX), 2,2,2-trifluoroethanol (TFE), and dimethyl sulfoxide (DMSO). Our analysis revealed that 5%–11% of all possible single substitutions (BSLA site-saturation mutagenesis (SSM) library) contribute to improved cosolvent resistance. However, only a fraction of these substitutions (7%–12%) could be detected in the three random mutagenesis libraries. To our knowledge, this is the first study that quantifies the capability of these diversity generation methods generally employed in directed evolution campaigns and compares them to the entire natural diversity with a single substitution. Additionally, the investigation of the BSLA SSM library revealed only few common beneficial substitutions for all three cosolvents as well as the importance of introducing surface charges for organic cosolvent resistance—most likely due to a stronger attraction of water molecules. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Open AccessArticle Efficient Hydrolysis of Lignocellulose by Acidic Ionic Liquids under Low-Toxic Condition to Microorganisms
Catalysts 2017, 7(4), 108; doi:10.3390/catal7040108
Received: 10 March 2017 / Revised: 4 April 2017 / Accepted: 6 April 2017 / Published: 7 April 2017
Cited by 1 | PDF Full-text (2372 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
Lignocellulose is known as a renewable resource, and acidic ionic liquids have been highlighted as efficient catalysts for hydrolysis of cellulose. To achieve successive hydrolysis and fermentation, efficient hydrolysis with sufficiently diluted acidic ionic liquids is necessary because acidic ionic liquids are toxic
[...] Read more.
Lignocellulose is known as a renewable resource, and acidic ionic liquids have been highlighted as efficient catalysts for hydrolysis of cellulose. To achieve successive hydrolysis and fermentation, efficient hydrolysis with sufficiently diluted acidic ionic liquids is necessary because acidic ionic liquids are toxic to fermentative microorganisms. Escherichia coli was confirmed to grow in 0.05 M dilute acidic ionic liquid—1-(1-butylsulfonic)-3-methylimidazolium hydrogen sulfate ([Sbmim][HSO4])—although the growth was suppressed in more concentrated solutions. Therefore, we applied the 0.05 M [Sbmim][HSO4] solution to hydrolysis of bagasse, leading to a glucose yield of 48% at 190 °C. This value is greater than that obtained with a concentrated [Sbmim][HSO4] solution, which is not suitable for the growth of Escherichia coli (yield: 40% in a 1.0 M solution). Efficient hydrolysis with acidic ionic liquids under low-toxic condition was achieved. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Review

Jump to: Research

Open AccessFeature PaperReview Catalytic Conversion of Carbohydrates to Furanic Derivatives in the Presence of Choline Chloride
Catalysts 2017, 7(7), 218; doi:10.3390/catal7070218
Received: 30 June 2017 / Revised: 12 July 2017 / Accepted: 13 July 2017 / Published: 20 July 2017
PDF Full-text (2655 KB) | HTML Full-text | XML Full-text
Abstract
The synthesis of furanic derivatives (5-hydroxymethylfurfural (HMF), furfural…) from carbohydrates is of high interest for a wide range of applications. These reactions are carried out in the presence of various solvents, and among them choline chloride can be used. It is a salt
[...] Read more.
The synthesis of furanic derivatives (5-hydroxymethylfurfural (HMF), furfural…) from carbohydrates is of high interest for a wide range of applications. These reactions are carried out in the presence of various solvents, and among them choline chloride can be used. It is a salt that can form a low melting mixture with a carbohydrate (fructose, glucose…) or a deep eutectic mixture with carboxylic acid. A review of the studies performed in the conversion of carbohydrates to furanic derivatives in the presence of choline chloride is presented here with the advantages and drawbacks of this solvent. Choline chloride can enhance the selectivity to HMF by stabilizing effect and allows the conversion of highly concentrated feed. However, the extraction of the products from these solvents still needs improvement. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Open AccessFeature PaperReview Bimetallic Nanoparticles in Alternative Solvents for Catalytic Purposes
Catalysts 2017, 7(7), 207; doi:10.3390/catal7070207
Received: 24 June 2017 / Revised: 4 July 2017 / Accepted: 5 July 2017 / Published: 7 July 2017
Cited by 1 | PDF Full-text (5038 KB) | HTML Full-text | XML Full-text
Abstract
Bimetallic nanoparticles represent attractive catalytic systems thanks to the synergy between both partners at the atomic level, mainly induced by electronic effects which in turn are associated with the corresponding structures (alloy, core-shell, hetero-dimer). This type of engineered material can trigger changes in
[...] Read more.
Bimetallic nanoparticles represent attractive catalytic systems thanks to the synergy between both partners at the atomic level, mainly induced by electronic effects which in turn are associated with the corresponding structures (alloy, core-shell, hetero-dimer). This type of engineered material can trigger changes in the kinetics of catalyzed processes by variations on the electrophilicity/nucleophilicity of the metal centers involved and also promote cooperative effects to foster organic transformations, including multi-component and multi-step processes. Solvents become a crucial factor in the conception of catalytic processes, not only due to their environmental impact, but also because they can preserve the bimetallic structure during the catalytic reaction and therefore increase the catalyst life-time. In this frame, the present review focuses on the recent works described in the literature concerning the synthesis of bimetallic nanoparticles in non-conventional solvents, i.e., other than common volatile compounds, for catalytic applications. Full article
(This article belongs to the Special Issue Catalysis in Innovative Solvents)
Figures

Journal Contact

MDPI AG
Catalysts Editorial Office
St. Alban-Anlage 66, 4052 Basel, Switzerland
E-Mail: 
Tel. +41 61 683 77 34
Fax: +41 61 302 89 18
Editorial Board
Contact Details Submit to Catalysts Edit a special issue Review for Catalysts
logo
loading...
Back to Top