Ionic Liquids in Polar Diels-Alder Reactions Using Carbocycles and Heterocycles as Dienophiles

Pedro, Mateus; Kneeteman, Maria; Claudia, Della Rosa; Virginia, Bravo; Adam, Claudia G.

doi:10.5772/20511

Cited by 1 publication

(2 citation statements)

References 38 publications

(29 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In recent decades, ionic liquids (ILs) have gained great importance as green solvents in organic synthesis and other chemical processes [1][2][3][4][5][6][7][8]. This is mainly due to the following reasons: (i) ILs have very good dissolution properties for most organic and inorganic compounds, (ii) they are stable at high temperatures, (iii) they have a vapour pressure close to zero and (iv) they are generally non-volatile and non-flammable.…”

Section: Introductionmentioning

confidence: 99%

“…In this context, several experimental and theoretical studies devoted to the study of DA reactions in ILs can be found in the literature [16][17][18][19][20][21][22][23][24][25][26][27][28]. For instance, Mancini et al [4] analysed the influence of protic ionic liquids (PILs) in thermal polar DA reactions in which the dienophiles are relatively poor, in order to obtain information about the factors affecting reactivity and selectivity. These authors demonstrated theoretically that the solvent effect of ILs in these reactions is, in general, determined by the solvent hydrogen bond donation ability.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Theoretical Investigation of the Kinetic Effect of the 1-Ethylpyridinium Trifluoroacetate Ionic Liquid in the Acceleration of Diels–Alder Reactions of Isoprene with Acrylic Acid and Acrylonitrile

Chemouri

Mekelleche

2017

Progress in Reaction Kinetics and Mechanism

View full text Add to dashboard Cite

The mechanism, the regioselectivity, the stereoselectivity and the kinetics of Diels–Alder reactions of isoprene with acrylic acid and acrylonitrile have been studied, at the B3PW91/6-31G(d,p) level of theory, both in the gas phase and in the presence of organic [dichloromethane (DCM)] and ionic liquid [1-ethylpyridinium trifluoroacetate (EPTFA)] solvents. Intrinsic reaction coordinate calculations show that these reactions take place through an asynchronous concerted mechanism leading to the endo para cycloadducts as the major products in the gas phase and to the exo para cycloadducts as the major products both in organic and in ionic liquid solvents. The explicit solvation model involving the coordination of one molecule of the solvent with the dienophiles shows a considerable decrease of the activation energy when passing from DCM to EPTFA. The enhancement of these cycloaddition reactions can be explained by the strong hydrogen bonding created between the ion pair of the ionic liquid and the oxygen atom of the dienophile reagents. Moreover, density functional theory-based reactivity indices also show an increase of the reaction polarity and consequently of the reaction rate, when replacing DCM solvent by EPTFA solvent. The results obtained give evidence that the ionic liquid EPTFA is an excellent solvent for Diels–Alder reactions in comparison with conventional organic solvents.

show abstract