Enantioselective Catalytic Conjugate Addition of Dialkylzinc Reagents using Copper–Phosphoramidite Complexes; Ligand Variation and Non-linear Effects
作者:Leggy A Arnold、Rosalinde Imbos、Alessandro Mandoli、André H.M de Vries、Robert Naasz、Ben L Feringa
DOI:10.1016/s0040-4020(00)00142-3
日期:2000.4
cyclohexenone and chalcone in order to assess the structural features that are important for stereocontrol. A sterically demanding amine moiety is essential to reach high e.e.’s. Enantioselectivities for chalcones up to 89% and for cyclic enones up to 98% were found. Studies on non-linear effects with the best ligands for both cyclohexenone and chalcone showed clear non-linear effects for both cyclic
Multinuclear Cu/Zn complex-catalyzed efficient asymmetric conjugateaddition of organozincreagents to acyclic and cyclic enones has been developed in the presence of a wide variety of regioisomeric chiral diols bearing phosphorus moieties as ligands. The regioisomeric SPINOL-PHOS ligands based on a SPINOL architecture showed an unexpected inversion of stereoselectivity.
The Cu-catalyzed asymmetric conjugate addition with chiral diphosphite ligands derived from <scp>D</scp>-(-)-tartaric acid
作者:Zeng-Bo Pang、Mi Tian、Hai-Feng Li、Lai-Lai Wang
DOI:10.1080/00397911.2016.1278231
日期:2017.3.19
diphosphite ligands, which were derivedfrom D-(-)-tartaric acid, have been synthesized and successfully applied in the Cu-catalyzed asymmetric conjugate addition of organozincs to enones. There was a synergic effect between the stereogenic centers of the D-(-)-tartaric acid skeleton and the axially H8-binaphthyl moieties of ligand 2c. And ligand 2c shows a comparative catalytic performance to ligand 1-N-benzylpyrrolidine-3
Synthesis of diphosphite ligands derived from glucopyranoside and their application in the Cu-catalyzed asymmetric 1,4-addition of organozinc to enones
作者:Qing-Lu Zhao、Man Kin Tse、Lai-Lai Wang、Ai-Ping Xing、Xianxing Jiang
DOI:10.1016/j.tetasy.2010.11.012
日期:2010.12
Novel chiral diphosphite ligands derived from glucopyranoside and H8-binaphthol were synthesized, and successfully employed in the Cu-catalyzed asymmetric 1,4-addition of organozinc reagents dimethylzinc, diethylzinc, and diphenylzinc to cyclic and acyclic enones with up to 96% ee. The stereochemically matched combination of d-glucopyranoside backbone and (R)-H8-binaphthyl in the ligand 2,4-bis[(R)-1
Copper-catalyzed enantioselective 1,4-conjugate addition of dialkylzinc reagents to α,β- and α,β,γ,δ-unsaturated ketones
作者:Rukeya Rexiti、Jian Lu、Feng Sha、Xin-Yan Wu
DOI:10.1016/j.tet.2019.05.029
日期:2019.6
An enantioselective Cu(II)-catalyzed conjugate addition of dialkylzinc reagents to α,β- or α,β,γ,δ-unsaturated ketones with chiral cyclohexane-based amidophosphine ligands was developed. With 2 mol% of Cu(OAc)2·H2O/L5, the conjugate addition of diethylzinc to α,β-unsaturated ketones was achieved in good-to-excellent yields (up to 98%) and high enantioselectivities (up to 92% ee). This catalytic system