Search results for "ionic liquid"

Selective palladium-catalysed dimerisation of methyl acrylate in ionic liquids: towards a continuous processThis work was presented at the Green Solv…

2003

The activity and stability of cationic palladium complexes [Pd(PBu3)2S2]2+ used for the selective tail-to-tail dimerisation of methyl acrylate are significantly improved with the utilisation of ionic liquids like [BMIM][BF4] or the protonated N-butyl-imidazole, [HBIM][BF4]. Problems related to product inhibition and catalyst recycling are overcome by running the reaction in a two-phase mode, toluene being used as extractant. Catalyst stabilisation is further improved by trapping the ancillary ligand into the ionic liquid with an ionic tail: with the use of 1-dibutylphosphino-2-dimethylaminoethane, the catalyst is stable for more than 100 h, therefore demonstrating the feasibility of a conti…

Fluorinated azole-azine systems as new Liquid-crystalline Ionic Liquids

2015

Nitropyrroles, Diels-Alder reactions assisted by microwave irradiation and solvent effect. An experimental and theoretical study

2017

The behaviors of N-tosylnitropyrroles acting as electrophilic dienophiles in polar Diels-Alder reactions joint to different dienes of increeased nucleophilicity are analyzed. The reactions were developed under microwave irradiation using toluene or protic ionic liquids (PILs) as solvents and in free solvent conditions. In all the cases explored we observed good yields in short reaction times. For these reactions, the free solvent condition and the use of protic ionic liquids as solvents offer similar results. However, the free solvent conditions favor environmental sustainability. The role of PILs in these polar Diels-Alder reactions has been theoretically studied within the Molecular Elect…

Effect of ionic liquids in acid-promoted heterocyclic rearrangement reaction

Reactivity of phenylhydrazones in ionic liquids solution: the effect of copper(II) salts

Multiple points of view of heteronuclear NOE: long range vs short range contacts in pyrrolidinium based ionic liquids in the presence of Li salts.

2015

The nuclear Overhauser enhancement (NOE) is a powerful tool of NMR spectroscopy extensively used to gain structural information in ionic liquids (ILs). A general model for the distance dependence of intermolecular NOE in ILs was recently proposed showing that NOE spots beyond the first solvation shell and accounts for long-range effects. This conclusion prompted for a deep rethinking of the NOE data interpretation in ILs. In this paper we present an extensive and quantitative study of N-propyl-N-methyl pyrrolidinium bis(trifluoromethanesulfonyl)imide (PYR13TFSI), the homologue with bis(fluorosulfonyl)imide (PYR13FSI), and their mixtures with LiTFSI based on 1H-19F and 1H-7LiNOE correlation …

Supported Ionic Liquids: A Versatile and Useful Class of Materials.

2017

Supported ionic liquids (SILs) represent a class of materials with peculiar properties and a huge potential regarding their possible applications in different fields of chemistry. Herein, we report our ongoing research about the use of SILs as support for organocatalysts, their role as catalysts themselves, and their application as support and stabilizers of palladium nanoparticles (PdNPs). The use of SILs based materials allowed achieving good results. Moreover, in some cases, after the functionalization of the catalytic species with an ion-tag moiety, a release and catch approach was employed in order to improve the catalytic activity and to facilitate the recovery of the hybrid system fo…

1,2,4-Triazolium ions as flexible scaffolds for the construction of polyphilic ionic liquid crystals

2018

A novel scaffold for the construction of self-organised ionic liquids and ionic liquid crystals bearing both perfluorocarbon and hydrocarbon moieties has been developed. The phase behaviour and physical properties of these materials can be tuned as a function of chain length and fluorine content and significant structural elaboration is possible, giving a highly flexible system.

Applicability of a Polymerized Ionic Liquid/Carbon Nanoparticle Composite Electrolyte to Reductive Cyclization and Dimerization Reactions

2016

Abstract Recently, a reusable polymerized ionic liquid/carbon nanoparticle composite electrolyte was developed and effectively applied to a variety of oxidative transformations. The efficient recovery of the composite material and its application in subsequent electroorganic conversions without sacrificing yield adds to the sustainability of the protocol. Herein, we describe our efforts to expand the operational window of the composite electrolyte to include cathodically initiated processes occurring at potentials up to −2.6 V. The results indicate that the composite electrolyte is applicable to reductive processes, but the scope of transformations appears to be limited.

An electrochemical process to prepare and recycle biobased ionic liquids

2019

This manuscript describes the first electrosynthesis of biobased ionic liquids from L-valine, oxalic acid and glyoxal, which is energy-efficient, does not emit toxic waste and avoids the formation of inorganic waste. These ionic liquids were then used in the development of our electro-recycling process. While their recycling yields are still moderated due to recombination and disproportionation reactions, this unprecedented recycling technology is very promising in terms of environmental and economic gains. Indeed, it has a high energy efficiency, requires low cost equipment, allows a strong decrease of the price of such ionic solvents, limits the use of non-renewable resources and solves t…