Wang, Guo-Peng; Chen, Meng-Qing; Zhu, Shou-Fei; Zhou, Qi-Lin published an article in 2017, the title of the article was Enantioselective Nazarov cyclization of indole enones cooperatively catalyzed by Lewis acids and chiral Bronsted acids.SDS of cas: 883526-76-9 And the article contains the following content:
The use of cooperative catalysis using Lewis acids and chiral Bronsted acids to control the stereochem. of the tertiary α-carbon I (R = H, 7-Me, 7-F, 7-Cl, 8-F; R1 = Me, Ph, 2H-1,3-benzodioxol-5-yl, etc.) in the products of this reaction has been reported. Specifically, with ZnCl2 and a chiral spiro phosphoric acid as catalysts, the first enantioselective construction of cyclopenta[b]indoles with chiral tertiary α-carbons I was realized via Nazarov cyclization of indole enone substrates II (R2 = H, 5-Me, 5-F, 5-Cl, 4-F) with only one coordinating site. Mechanistic studies revealed that the chiral spiro phosphoric acid acts as a multifunctional catalyst and it co-catalyzes the cyclization of the dienone and enantioselectively catalyzes a proton transfer reaction of the enol intermediate. This new strategy of enantioselective control by means of cooperative catalysis may show utility for other challenging asym. cyclization reactions. The experimental process involved the reaction of 1,5-Dimethyl-1H-indole-2-carbaldehyde(cas: 883526-76-9).SDS of cas: 883526-76-9
The Article related to cyclopentaindole preparation enantioselective, indole enone nazarov cyclization lewis acid chiral phosphoricacid catalyst, Heterocyclic Compounds (One Hetero Atom): Indoles, Indolizines, Carbazoles, and Other Arenopyrroles and other aspects.SDS of cas: 883526-76-9
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Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles