Lewis Acid Catalyzed Cyclization of Glycals/2-Deoxy-d-ribose with Arylamines: Additional Findings on Product Structure and Reaction Diastereoselectivity

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• 作者：Chengtang Du ; Fulong Li ; Xuefeng Zhang ; Wenxiang Hu ; Qizheng Yao ; Ao Zhang
• 刊名：Journal of Organic Chemistry
• 出版年：2011
• 出版时间：November 4, 2011
• 年：2011
• 卷：76
• 期：21
• 页码：8833-8839
• 全文大小：437K
• 年卷期：v.76,no.21(November 4, 2011)
• ISSN：1520-6904

文摘

The cyclization reactions of arylamines with 2-deoxy-d-ribose or glycals were reinvestigated in the current report. In the montmorillonite KSF- or InCl₃-initiated reactions of 2-deoxy-d-ribose with arylamines, a pair of diastereomeric tetrahydro-2H-pyran-fused tetrahydroquinolines was obtained in a nearly 1:1 ratio where the structure of one diastereomer was incorrectly assigned in the literature. Meanwhile, the diastereoselectivity in InBr₃-catalyzed cyclization of glycals with arylamines was also incorrectly reported previously. It was found that high diastereomeric selectivity was achieved only when a C5-substituted glycal was used; otherwise, a pair of diastereomers was obtained in moderate yield with 1:1 diastereomeric ratio. Furthermore, tetrahydrofuran-fused tetrahydroquinolines 5b and 5b鈥?/b> were also prepared successfully by using TBDPS-protected ribose as the glycal precursor and montmorillonite KSF as the activator.