Enantioselective Allylation of Alkenyl Boronates Promotes a 1,2-Metalate Rearrangement with 1,3-Diastereocontrol
作者:Colton R. Davis、Irungu K. Luvaga、Joseph M. Ready
DOI:10.1021/jacs.1c01242
日期:2021.4.7
Alkenyl boronates add to Ir(π-allyl) intermediates with high enantioselectivity. A 1,2-metalate shift forms a second C–C bond and sets a 1,3-stereochemical relationship. The three-component coupling provides tertiary boronic esters that can undergo multiple additional functionalizations. An extension to trisubstituted olefins sets three contiguous stereocenters.
Copper-Catalyzed Asymmetric Conjugate Addition of Trialkylaluminium Reagents to Trisubstituted Enones: Construction of Chiral Quaternary Centers
作者:Magali Vuagnoux-d'Augustin、Alexandre Alexakis
DOI:10.1002/chem.200701001
日期:2007.11.26
vinylalane species undergo enantioselective conjugateaddition to a wide range of 2- or 3-substituted enones (cyclopent-2-enones, cyclohex-2-enones, 3-methyl cyclohept-2-enone) in the presence of catalytic amount of copper salt (copper thiophene carboxylate, [Cu(CH3CN)4]BF4 or [CuOTf]2C6H6) and tropos-phosphoramidite-based ligand. Thus, chiral quaternarycenters can be built, with up to 98% ee after rigorous
Kinetic Study of Various Phosphoramidite Ligands in the Iridium-Catalyzed Allylic Substitution
作者:Damien Polet、Alexandre Alexakis
DOI:10.1021/ol050350w
日期:2005.4.14
[reaction: see text] A comparative kineticstudy of seven ligands is presented which clearly shows that a slight difference in the substitution pattern of the aryl group on the amine moiety of the ligand dramatically alters the activity of the resulting iridium catalyst. Ligand L6 shows the most impressive kinetics as well as the highest enantioselectivities.