Rationalisation of solvent effects in the diels-alder reaction between cyclopentadiene and methyl acrylate in room temperature ionic liquids

The Diels-Alder reaction between cyclopentadiene and methyl acrylate in ionic liquids has been studied in detail. The effect of contamination of the ionic liquids by common impurities, viz. sodium and chloride ions, and water, on the selectivity has been investigated. The presence of high concentrations of chloride was found to decrease the selectivity. Anion and, in particular, cation effects have been investigated using an extensive series of air-stable room temperature ionic liquids, and kinetic parameters have been determined. It has been found that strongly interacting groups, particularly electrophilic moieties on the cation, accelerate the formation of the endo products. Substrate solubility intimately connected to the selectivity was found to be mainly anion dependent. An NMR-based solvent parameter scale and semi-empirical models are used to analyse the results and provide a tool for the prediction of selectivities in ionic liquids.

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Paul Joseph Dyson, Gabor Laurenczy, Ana Vidis
2005
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https://infoscience.epfl.ch/record/59858?ln=en

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Related publications

Carbon monoxide solubility in ionic liquids: determination, prediction and relevance to hydroformylation

Paul Joseph Dyson, Gabor Laurenczy

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Paul Joseph Dyson, Zhaofu Fei, Dongbin Zhao

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Paul Joseph Dyson, Gabor Laurenczy, Dongbin Zhao

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2004

Ionic liquid

An ionic liquid (IL) is a salt in the liquid state. In some contexts, the term has been restricted to salts whose melting point is below a specific temperature, such as . While ordinary liquids such

Ion

An ion (ˈaɪ.ɒn,_-ən) is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of

Diels–Alder reaction

In organic chemistry, the Diels–Alder reaction is a chemical reaction between a conjugated diene and a substituted alkene, commonly termed the dienophile, to form a substituted cyclohexene derivative