Diastereoselective construction of 4-indole substituted chromans bearing a ketal motif through a three-component Friedel–Crafts alkylation/ketalization sequence. Issue 28 (25th April 2018)

• Record Type: Journal Article
• Authors: Guo, Jiao-Mei; Wang, Wen-Bo; Guo, Jia; Zhu, Yan-Shuo; Bai, Xu-Guan; Jin, Shao-Jing; Wang, Qi-Lin; Bu, Zhan-Wei
• Is Part Of: RSC advances. Volume 8:Issue 28(2018)
• Page Start: 15641
• Page End: 15651
• Publication Date: 2018-04-25
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c8ra02481b
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : The first TfOH-catalyzed three-component Friedel–Crafts alkylation/ketalization sequence of indoles, alcohols and ortho -hydroxychalcones was developed to afford a wide range of 4-indole substituted chromans bearing a ketal motif in 77–99% yields. Abstract : The first TfOH-catalyzed three-component Friedel–Crafts alkylation/ketalization sequence of indoles, alcohols and ortho -hydroxychalcones was developed to afford a wide range of 4-indole substituted chromans bearing a ketal motif in 77–99% yields. Notably, only a simple filtration was needed to purify them. By altering methanol to CHCl3, 2, 4-bisindole substituted chroman with the same indole substituent at the C2 and C4 positions was afforded. Moreover, 2, 4-bisindole substituted chromans with different indole substituents could be obtained by treatment of 4-indole monosubstituted chromans with another indole molecule.