503111-31-7Relevant academic research and scientific papers
Recycling of allylic alkylation Pd catalysts containing phosphine-imidazoline ligands in ionic liquids
De La Fuente, Veronica,Fleury-Bregeot, Nicolas,Claver, Carmen,Castillon, Sergio
, p. 2715 - 2718,4 (2020/09/14)
An efficient catalytic system to perform allylic alkylation in ionic liquids based on a Pd/phosphine imidazoline system has been designed. This system affords very good results (ee's up to 95%) when used with the appropriate ionic liquid as well as under microwave conditions. Recycling experiments were conducted showing very promising results.
Zwitterionic iridium complexes with P,N-ligands as catalysts for the asymmetric hydrogenation of alkenes
Franzke, Axel,Pfaltz, Andreas
, p. 4131 - 4144 (2011/06/21)
Several zwitterionic iridium complexes based on chiral P,N-ligands with imidazoline or oxazoline donors and anionic tetraarylborate or aryltrifluoroborate substituents have been synthesized. The corresponding cationic analogues have also been prepared, to evaluate the effect of the covalent linkage between the anion and the cationic metal complex in catalytic reactions. The respective pairs of structurally analogous precatalysts have been compared for their efficacies in the asymmetric hydrogenation of unfunctionalized olefins. In most cases, the anionic derivatization has virtually no influence on the asymmetric induction of the iridium complex. This is in accordance with X-ray structural studies, which have shown that the chiral environment of the cationic metal center is not affected by the anionic substituent. Depending on the nature of the counterion employed, the zwitterionic catalysts proved to be significantly more reactive than their cationic counterparts in nonpolar solvents. Copyright
Changing the palladium coordination to phosphinoimidazolines with a remote triazole substituent
De La Fuente, Veronica,Marcos, Rocio,Cambeiro, Xacobe C.,Castillon, Sergio,Claver, Carmen,Pericas, Miquel A.
supporting information; scheme or table, p. 3255 - 3261 (2012/01/17)
Phosphinoimidazoline (PHIM) ligands bearing a triazolylmethyl substituent at the sp3 nitrogen atom in the imidazoline ring lead to highly improved enantioselectivity (up to 99% ee) in allylic substitution reactions with respect to analogous ligands with substituents lacking the triazole unit. NMR and theoretical studies support a shift in the coordination mode of the PHIM ligand to palladium, triggered by a very favourable interaction with the triazole unit. Copyright
An efficient method for the synthesis of enantiopure phosphine-imidazoline ligands: Application to the Ir-catalyzed hydrogenation of imines
Guiu, Ester,Claver, Carmen,Benet-Buchholz, Jordi,Castillon, Sergio
, p. 3365 - 3373 (2007/10/03)
Phosphine-imidazoline ligands 8, and the derivatives 16 and 17, which have electron-withdrawing or electron-donating groups in the aminic nitrogen, were synthesized from 2-aryl-imidazolines, which have previously been obtained from dithioesters. The coord
Probing electronic effects in the asymmetric Heck reaction with the BIPI ligands.
Busacca, Carl A,Grossbach, Danja,So, Regina C,O'Brien, Erin M,Spinelli, Earl M
, p. 595 - 598 (2007/10/03)
[structure: see text] The new BIPI ligands are phosphinoimidazolines that can be electronically tuned in three different ligand regions to explore electronic effects in asymmetric catalysis. Their application to the asymmetric Heck reaction (AHR) in the c
