84235-36-9Relevant academic research and scientific papers
The effect of alumina on the Diels-Alder reactions of cyclopentadiene with menthyl acrylate and dimenthyl fumarate
Kabalka,Pagni,Bains,Hondrogiannis,Plesco,Kurt,Cox,Green
, p. 1283 - 1294 (1991)
Alumina catalyzes the Diels-Alder reactions of cyclopentadiene with optically active menthyl acrylate and dimenthyl fumarate. Significant diastereoselectivity is observed in each case.
Solvent effects on Diels-Alder reactions. the use of aqueous mixtures of fluorinated alcohols and the study of reactions of acrylonitrile
Cativiela, Carlos,Garcia, Jose I.,Gil,Martinez, Rosa M.,Mayoral, Jose A.,Salvatella, Luis,Urieta, Jose S.,Mainar,Abraham, Michael H.
, p. 653 - 660 (2007/10/03)
Rate, endolexo, regio- and diastereo-facial selectivities of several Diels-Alder reactions were measured in a series of fluorinated alcohol-water mixtures, whose solvophobicity has been determined by means of the solvophobic power (Sp) parameter. Solvophobicity is the main factor influencing the reaction rate, although in some reactions hydrogen bond donating (HBD) ability may also play a role. Both solvophobicity and HBD ability are important to account for changes in endolexo selectivity. HBD ability is the main factor responsible for the changes in regio- and diastereo-facial selectivities, induced by the reaction medium. On the other hand, the kinetic rate constants and endolexo selectivity of the reaction of acrylonitrile with cyclopentadiene, as well as the regioselectivity of the reaction of acrylonitrile with isoprene, have been determined in 23 reaction media. The analysis of the results using empirical solvent parameters show that the reaction rate depends on solvophobic, HBD and dipolarity interactions, whereas endolexo selectivity is influenced by solvophobic and dipolarity interactions, and the regioselectivity only by HBD effects.
Silica and alumina modified by Lewis acids as catalysts in Diels-Alder reactions of chiral acrylates
Cativiela,Figueras,Garcia,Mayoral,Pires,Royo
, p. 621 - 624 (2007/10/02)
Silica and alumina, modified by treatment with AlClEt2 and TiCl4, are tested as catalysts in the reactions of cyclopentadiene (1) with (-)-methyl acrylate (2a), (R)-O-acryloyl pantolactone (2b) and (S)-O-acryloyl lactate (2c). Silica-modified systems are the most efficient heterogeneous catalysts described to date for this kind of reaction, leading to selectivities similar to those obtained with aluminium homogeneous catalysts. Whereas silica· AlClEt2 is better for the reaction of 2a and 2c, silica· TiCl4 is more suitable for the reaction of 2b.
Effect of clay calcination on clay-catalysed Diels-Alder reactions of cyclopentadiene with methyl and (-)-menthyl acrylates
Cativiela, Carlos,Fraile, Jose M.,Garcia, Jose I.,Mayoral, Jose A.,Pires, Elisabeth,Figueras, Francois,De Menorval, Louis C.
, p. 6467 - 6476 (2007/10/02)
Zn(II) and Fe(III)-exchanged K 10-montmorillonites, activated by several methods, are used as catalysts in the reaction between methyl acrylate and cyclopentadiene. Calcined clays are better catalysts than dried clays. Zn(II) clays, dried and calcined, are compared as catalysts of the asymmetric Diels-Alder reaction between (-)-methyl acrylate and cyclopentadiene. Calcined clay again shows a higher catalytic activity and leads to better percentages of diastereomeric excess. Furthermore, calcined clays are easily recovered with no loss of catalytic properties.
Clay-catalysed asymmetric Diels-Alder reaction of cyclopentadiene with (-)-menthyl acrylate
Cativiela,Figueras,Fraile,Garcia,Mayorall
, p. 953 - 956 (2007/10/02)
Zn(II)-exchanged K10 montmorillonite is shown to be an efficient catalyst for the reaction between cyclopentadiene and (-)-menthyl acrylate, leading to the 1R,2R-cycloadduct with good chemical yield, high % d.e. and excellent endo/exo selectivity.
The reaction of optically active menthyl acrylate with cyclopentadiene on γ-alumina
Hondrogiannis,Pagni,Kabalka,Kurt,Cox
, p. 2303 - 2306 (2007/10/02)
The Diels-Alder reaction of optically active menthyl acrylate with cyclopentadiene is catalyzed by γ-alumina. The reaction is very selective, yielding large endo to exo ratios of products and diastereomeric excesses for the endo adduct.
A REINVESTIGATION OF ASYMMETRIC INDUCTION IN DIELS-ALDER REACTIONS
Oppolzer, Wolfgang,Kurth, Mark,Reichlin, Daniel,Moffatt, Frank
, p. 2545 - 2548 (2007/10/02)
The chiral induction in the Diels-Alder addition 12, assessed reliably by (19)F-NMR-spectroscopy of the endo-esters 4, varied between 47-93 percent in favor of the 2-(R)-adducts 2 depending on the auxiliary chiral group and the Lewis-acid catalyst.
