Monodentate N-Ligand-Directed Bifunctional Transition-Metal Catalysis: Highly Enantioselective Friedel-Crafts Alkylation of Indoles with Nitroalkenes
作者:Fengfeng Guo、Guoyin Lai、Shunshun Xiong、Sujing Wang、Zhiyong Wang
DOI:10.1002/chem.201000540
日期:2010.6.11
A role beyond base: A highly efficient, asymmetric Friedel–Craftsalkylation of indoles with nitroalkenes is presented that uses simple nitrogen compounds combined with Schiff base zinc(II) complexes as bifunctional catalysts (see scheme). The nitrogen compounds here play a crucial role as ligands as well as their traditional role as bases.
Chiral Phosphoric Acid Catalyzed Asymmetric Friedel–Crafts Alkylation of Indoles with Nitroolefins
作者:Hong-Ying Tang、Zhong-Biao Zhang
DOI:10.1080/10426507.2010.536189
日期:2011.10
Abstract Asymmetric Michael-type Friedel–Crafts (F–C) alkylations of indoles with nitroolefins catalyzed by a chiral H8-BINOL-based phosphoricacid were investigated. The reactions took place very smoothly in the presence of only 5 mol-% of catalyst at room temperature to afford the desired F–C alkylation products in good yields and with moderate enantioselectivities. GRAPHICAL ABSTRACT
A New Type of Bis(sulfonamide)-Diamine Ligand for a Cu(OTf)<sub>2</sub>-Catalyzed Asymmetric Friedel–Crafts Alkylation Reaction of Indoles with Nitroalkenes
作者:Jing Wu、Xincheng Li、Fan Wu、Boshun Wan
DOI:10.1021/ol201914r
日期:2011.9.16
Chiral bis(sulfonamide)-diamine served as new type of ligand for a Cu(OTf)2-catalyzed asymmetricFriedel–Craftsalkylation reaction of indoles with nitroalkenes. The desired products were obtained with up to 99% yield and 97% ee.
Orthogonal Enantioselectivity Approaches Using Homogeneous and Heterogeneous Catalyst Systems: Friedel-Crafts Alkylation of Indole
作者:Hun Young Kim、Sungkyung Kim、Kyungsoo Oh
DOI:10.1002/anie.201001484
日期:2010.6.14
With or without support? The complementary homogeneous and heterogeneouscatalystsystems have been developed for the catalytic asymmetric Friedel–Craftsalkylation of indoles with nitroalkenes, in which either of the enantiomeric products 2 could be selectively obtained under the suitable reaction conditions (i.e. with or without an added solid support; see scheme).