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
Enantioselective Friedel-Crafts alkylation of indole with nitroalkenes in the presence of bifunctional squaramide organocatalysts
作者:Esra Dündar、Cihangir Tanyeli
DOI:10.1016/j.tetlet.2021.153153
日期:2021.6
A series of chiral bifunctional quinine and 2-aminoDMAP based squaramide organocatalysts are evaluated in Friedel-Craftsalkylation of indoles with nitroolefins. These 3-substituted indole derivatives are synthesized in the presence of sterically encumbered tert-butyl squaramide/quinine with high enantioselectivity (up to >99% ee) and moderate chemical yields (up to 80%) by representing as chiral precursors
Catalytic Enantioselective Additions of Indoles to Nitroalkenes
作者:Madhu Ganesh、Daniel Seidel
DOI:10.1021/ja8063292
日期:2008.12.10
A new design principle that provides access to more active thiourea catalysts is described. Highly enantioselective additions of indoles to nitroalkenes are reported using a new quinolinium thioamide catalyst.