Cu-Catalyzed Asymmetric Conjugate Additions of Alkylzinc Reagents to Acyclic Aliphatic Enones
作者:Hirotake Mizutani、Sylvia J. Degrado、Amir H. Hoveyda
DOI:10.1021/ja0122849
日期:2002.2.1
Cu-catalyzed enantioselective conjugate additions to acyclic aliphatic enones are reported. The resulting enolates may be functionalized intra- and intermolecularly, leading to the formation of an additional C-C bond. The utility of the present method is not limited to reactions involving Et2Zn; a variety of alkylzincs may be used. Moreover, many of the requisite substrates can be easily accessed through
报道了铜催化的对映选择性共轭添加到无环脂肪族烯酮。所得的烯醇可以在分子内和分子间进行功能化,从而形成额外的 CC 键。本方法的用途不限于涉及 Et2Zn 的反应;可以使用多种烷基锌。此外,许多必需的底物可以通过催化烯烃交叉复分解轻松获得。
Copper-catalyzed enantioselective conjugate addition of diethylzinc to acyclic enones with chiral sulfoxide–phosphine ligands
The copper-catalyzed enantioselectiveconjugateaddition of diethylzinc to acyclic enones was achieved with chiral sulfoxide–phosphine (SOP) ligands. This process showed good functional group tolerance and gave the 1, 4-adducts with excellent enantioselectivities (up to 96% ee).
Syntheses of simple TADDOL-like phosphite, phosphonite and phosphonate chiral ligands
作者:Jesica P. Perotti、Raquel M. Cravero、Liliana E. Luna、Ricardo J. A. Grau、Santiago E. Vaillard
DOI:10.3998/ark.5550190.0012.b09
日期:——
New simplephosphite, phosphonite and phosphonatechiralligands derived from DIMPTH(OH)2 and rigid bis-DIMPTH(OH)2 were prepared with moderate to good yields (35-86%) from readily available starting materials. The syntheses of the new chiralligands required the use of Et3N as base, since the use of more nucleophilic DIMPTH(OH)2 alkoxides precluded the formation of the ligands. Representative ligands
optically active molecules. Procedures that employ chiral homogeneous catalysts have been developed extensively, but ones that use chiral heterogeneouscatalysts are less explored and remain a challenge. Here we report a polymer-supported chiral heterogeneous copper catalyst that demonstrated high reactivity and enantioselectivity in asymmetric conjugate addition reactions of both ketones and imines. It was
Chiral dinuclear phthalazine bridged bisoxazoline ligands: synthesis and application in enantioselective Cu-catalyzed conjugate addition of ZnEt2 to enones
A new class of chiral dinuclear ligands with phthalazine bridged bisoxazoline scaffold was designed and prepared in convenient synthetic routes. H-1 NMR analysis showed that this class of ligands could coordinate with two metal ions, either same or different. These ligands afforded good to excellent yields and enantioselectivities in Cu-catalyzed conjugate addition of ZnEt2 to enones. (C) 2011 Elsevier Ltd. All rights reserved.