Cross‐Coupling Reaction of Alkenyl Sulfoximines and Alkenyl Aminosulfoxonium Salts with Organozincs by Dual Nickel Catalysis and Lewis Acid Promotion
作者:Irene Erdelmeier、Gerd Bülow、Chang‐Wan Woo、Jürgen Decker、Gerhard Raabe、Hans‐Joachim Gais
DOI:10.1002/chem.201901163
日期:2019.6.21
atom. CCR of axially chiral alkenyl sulfoximines with Ni(PPh3)2Cl2 as a precatalyst and ZnPh2 does not require salt promotion and is stereoretentive. The reaction with Zn(CH2SiMe3)2, however, demands salt promotion and is not stereoretentive. CCR of axially chiral α‐methylated alkenyl sulfoximines afforded persubstituted axially chiral alkenes with high selectivity. Alkenyl (N‐triflyl)sulfoximines
本文描述了环外,轴向手性和无环烯基(N-甲基)亚磺酰亚胺与烷基锌和芳基锌的交叉偶联反应(CCR)。CCR通常需要双重Ni催化和MgBr 2促进作用,这在乙醚中有效,但在THF中无效。NMR光谱显示,MgBr 2在乙醚中使烯基亚砜亚胺络合,这表明通过核真菌活化可加快氧化加成反应。烯基亚砜肟的CCR通常在Ni(dppp)Cl 2作为前催化剂和MgBr 2的存在下进行在C和S原子上具有高度立体保留的烷基和芳基锌。以Ni(PPh 3)2 Cl 2为前催化剂和ZnPh 2的轴向手性烯基亚磺酰亚胺的CCR不需要盐促进,并且具有立体保持性。但是,与Zn(CH 2 SiMe 3)2的反应需要盐促进,并且不是立体保持性的。轴向手性α-甲基链烯基亚砜亚胺的CCR可提供高选择性的全取代轴向手性烯烃。烯基(N-三氟乙)亚砜肟与格利雅试剂和Ni(PPh 3)2 Cl 2参与立体保持性CCR。镍催化和MgBr 2的促进的CCR