31006-98-1Relevant academic research and scientific papers
Extending the substrate scope of bicyclic p-oxazoline/thiazole ligands for ir-catalyzed hydrogenation of unfunctionalized olefins by introducing a biaryl phosphoroamidite group
Biosca, Maria,Paptchikhine, Alexander,P??mies, Oscar,Andersson, Pher G.,Di??guez, Montserrat
, p. 3455 - 3464 (2015/03/04)
This study identifies a series of Ir-bicyclic phosphoroamidite-oxazoline/thiazole catalytic systems that can hydrogenate a wide range of minimally functionalized olefins (including E- and Z-tri- and disubstituted substrates, vinylsilanes, enol phosphinates, tri- and disubstituted alkenylboronic esters, and ?±,?2-unsaturated enones) in high enantioselectivities (ee values up to 99%) and conversions. The design of the new phosphoroamidite-oxazoline/thiazole ligands derives from a previous successful generation of bicyclic N-phosphane-oxazoline/thiazole ligands, by replacing the N-phosphane group with a p-acceptor biaryl phosphoroamidite moiety. A small but structurally important family of Ir-phosphoroamidite-oxazoline/thiazole precatalysts has thus been synthesized by changing the nature of the Ndonor group (either oxazoline or thiazole) and the configuration at the biaryl phosphoroamidite moiety. The substitution of the N-phosphane by a phosphoroamidite group in the bicyclic N-phosphane-oxazoline/thiazole ligands extended the range of olefins that can be successfully hydrogenated.
Synergistic interplay of a non-heme iron catalyst and amino acid coligands in H2O2 activation for asymmetric epoxidation of α-alkyl-substituted styrenes
Cuss, Olaf,Ribas, Xavi,Lloret-Fillol, Julio,Costas, Miquel
supporting information, p. 2729 - 2733 (2015/03/04)
Highly enantioselective epoxidation of α-substituted styrenes with aqueous H2O2 is described by using a chiral iron complex as the catalyst and N-protected amino acids (AAs) as coligands. The amino acids synergistically cooperate with the iron center in promoting an efficient activation of H2O2 to catalyze epoxidation of this challenging class of substrates with good yields and stereoselectivities (up to 97% ee) in short reaction times.
Studies on the 1,2-migrations in Pd-catalyzed negishi couplings with JosiPhos ligands
Lindhardt, Anders T.,G?gsig, Thomas M.,Skrydstrup, Troels
supporting information; experimental part, p. 135 - 143 (2009/04/07)
(Chemical Equation Presented) We report an initial investigation with the goal of determining the factors that control the 1,2-migration in the Negishi cross-coupling, which is promoted by palladium catalyst systems generated with JosiPhos ligands. Severa
A ligand free and room temperature protocol for Pd-catalyzed kumada-corriu couplings of unactivated alkenyl phosphates
Gauthier, Delphine,Beckendorf, Stephan,Gogsig, Thomas M.,Lindhardt, Anders T.,Skrydstrup, Troels
supporting information; experimental part, p. 3536 - 3539 (2009/09/30)
Kumada - Corriu cross-couplings of nonactivated cyclic and acyclic vinyl phosphates with aryl magnesium reagents afforded a series of 1,1-disubtituted alkenes in good yields for most cases when the reactions were performed at room temperature with the sim
Substituent effects on the solvolysis rates and gas phase stabilities of 1,2,2-trimethyl-1-phenylpropyl and 1,2,2-trimethyl-1-(2-methylphenyl)propyl systems
Nakata, Kazuhide,Fujio, Mizue,Mishima, Masaaki,Nomura, Hideyuki,Tsuno, Yuho,Nishimoto, Kichisuke
, p. 581 - 590 (2007/10/03)
Substituent effects on the solvolysis rates of 1,2,2-trimethyl-1- phenylpropyl chlorides in 80% (v/v) aq acetone at 45 °C and 1,2,2-trimethyl- 1-(2-methylphenyl)propyl p-nitrobenzoates in 50% (v/v) aq ethanol at 75 °C were correlated with the Yukawa-Tsuno
