Chiral Phosphoric-Acid-Catalyzed Regioselective and Enantioselective C7-Friedel-Crafts Alkylation of 4-Aminoindoles with Trifluoromethyl Ketones was written by Cai, Lu;Zhao, Yunlong;Huang, Tongkun;Meng, Shanshui;Jia, Xian;Chan, Albert S. C.;Zhao, Junling. And the article was included in Organic Letters in 2019.Reference of 85696-95-3 This article mentions the following:
A highly regioselective and enantioselective C7-Friedel-Crafts alkylation of 4-aminoindoles with trifluoromethyl ketones promoted by a spirocyclic phosphoric acid was developed. This strategy was applicable to various substituted trifluoromethyl ketones and 4-aminoindole derivatives, affording the corresponding C7-functionalized indole derivatives, bearing a pharmaceutically interesting trifluoromethylated tertiary alc. scaffold, in 21%-98% yields with up to >99% enantiomeric excess (ee). In the experiment, the researchers used many compounds, for example, 1-Methyl-1H-indol-4-amine (cas: 85696-95-3Reference of 85696-95-3).
1-Methyl-1H-indol-4-amine (cas: 85696-95-3) belongs to indole derivatives. Indole is an important structural motif of various drugs, therapeutic leads besides its prevalence in numerous natural products, agrochemicals, perfumery, and dyes. It is used in perfumery and in making tryptophan, an essential amino acid, and indoleacetic acid (heteroauxin), a hormone that promotes the development of roots in plant cuttings.Reference of 85696-95-3
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Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles