Br2 as a novel Lewis acid catalyst for Friedel–Crafts alkylation of indoles with α, β-unsaturated ketones. Issue 9 (2nd March 2016)

• Record Type: Journal Article
• Authors: Liang, Deqiang; Li, Xiangguang; Zhang, Wanshun; Li, Yanni; Zhang, Mi; Cheng, Ping
• Is Part Of: Tetrahedron letters. Volume 57:Issue 9(2016)
• Page Start: 1027
• Page End: 1030
• Publication Date: 2016-03-02
• Subjects: Homogeneous catalysis -- C–C coupling -- Alkylation -- Bromine effect -- Indole functionalization; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2016.01.078
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: The inexpensive Br2 can serve as a novel Lewis acid catalyst for Friedel–Crafts alkylation of indoles with α, β-unsaturated ketones. Under the catalysis of only 3 mol % of Br2, this Michael addition proceeded smoothly with high efficiency and broad substrate scope. Moreover, theoretical calculations suggested that Br2 possesses only the modest power to activate chalcones and is inferior to most tested acids, indicating that acidity might not be the primary cause for the unique activity of Br2 in the current communication.