Catalytic Enantioselective Friedel−Crafts Reactions of Aromatic Compounds with Glyoxylate: A Simple Procedure for the Synthesis of Optically Active Aromatic Mandelic Acid Esters
enantioselective Friedel−Craftsreaction of aromaticcompounds with glyoxylate catalyzed by chiral Lewis acids is presented. The reaction has been developed for mainly aromatic amines reacting with ethyl glyoxylate in the presence of chiral bisoxazoline−copper(II) complexes as the catalyst. A series of chiral bisoxazoline−copper(II) complexes have been tested as catalysts for the reaction with N,N-dimethylaniline
提出了在手性路易斯酸催化下芳族化合物与乙醛酸的第一个催化高度对映选择性 Friedel-Crafts 反应。在手性双恶唑啉-铜 (II) 配合物作为催化剂存在下,该反应主要用于芳香胺与乙醛酸乙酯反应。已经测试了一系列手性双恶唑啉-铜 (II) 配合物作为与 N,N-二甲基苯胺反应的催化剂,并且发现高度区域选择性和对映选择性的 Friedel-Crafts 反应发生在特别是叔-丁基双恶唑啉-铜(II)。该反应以高达 95% 的产率和 94% 的 ee 仅形成对位取代的异构体进行。已经研究了 N 的反应,N-二甲基苯胺在不同的反应条件下,已发展成为间位取代的 N,N-二甲基苯胺的催化高度对映选择性反应,含有吸电子或给电子取代基。该目录...
Enantioselective Friedel-Crafts Alkylation of Indoles, Pyrroles, and Furans with Trifluoropyruvate Catalyzed by Chiral Phosphoric Acid
Indoles, and pyrroles, and furans, oh my! Chiral phosphoric acidcatalyzed Friedel–Crafts alkylation of indoles with 3,3,3‐trifluoropyruvate gave the corresponding adducts in excellent yields with high enantioselectivities. Electron‐deficient indoles, in particular, exhibited excellent enantioselectivities.
Rapid and convenient synthesis of aryl- and heteroaryl-α-hydroxy-α-trifluoromethyl acetate via Friedel–Crafts alkylation under solvent- and catalyst-free conditions
作者:Jun-Ling Zhao、Li Liu、Hai-Bo Zhang、Yan-Chao Wu、Dong Wang、Yong Jun Chen
DOI:10.1016/j.tetlet.2006.02.054
日期:2006.4
Solvent- and catalyst-free Friedel–Crafts alkylation reactions of aromatic and heteroaromatic compounds with methyl trifluoropyruvate (2) were carried out at room temperature and finished in several minutes with good to excellent yields of the addition products (69→99%), which provided a rapid and convenient method to synthesize aryl- and heteroaryl-α-hydroxy-α-triflouromethyl acetates.