Tetrahedron letters

Efficient synthesis of trisubstituted [1] benzopyrano [4, 3-b] pyrrol-4 (1H)-one derivatives from 4-hydroxycoumarin

YX Liao, PY Kuo, DY Yang

文献索引：Liao, Yuan-Xiu; Kuo, Pei-Yu; Yang, Ding-Yah Tetrahedron Letters, 2003 , vol. 44, # 8 p. 1599 - 1602

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被引用次数: 20

摘要

Various trisubstituted [1] benzopyrano [4, 3-b] pyrrol-4 (1H)-one derivatives have been synthesized from 4-hydroxycoumarin with a 30–40% yield over six steps. The key step of the synthesis is a base-promoted intramolecular cyclization of enamines 5, followed by dehydration to generate the fused pyrrole ring.