An unexpected tetracyclic product isolated during the synthesis of biscoumarins catalyzed by [MIM(CH2)4SO3H][HSO4]: Characterization and X-ray crystal structure of 7-(2-hydroxy-4-oxo-4H-chromen-3-yl)-6H,7H-chromeno[4,3-b]chromen-6-one期刊界 All Journals 搜尽天下杂志传播学术成果专业期刊搜索期刊信息化学术搜索

按检索

An unexpected tetracyclic product isolated during the synthesis of biscoumarins catalyzed by [MIM(CH₂)₄SO₃H][HSO₄]: Characterization and X-ray crystal structure of 7-(2-hydroxy-4-oxo-4H-chromen-3-yl)-6H,7H-chromeno[4,3-b]chromen-6-one

Authors:	Niloofar Tavakoli-Hoseini Majid M HeraviFatemeh F Bamoharram Abolghasem DavoodniaMitra Ghassemzadeh

Institution:	^a Department of Chemistry, Mashhad Branch, Islamic Azad University, Mashhad, Iran ^b Department of Chemistry, School of Sciences, Azzahra University, Vanak, Tehran, Iran ^c Chemistry and Chemical Engineering Research Center of Iran, PO Box 14335-186, Tehran, Iran

Abstract:	Under solvent-free conditions and in the presence of 3-methyl-1-(4-sulfonic acid)butylimidazolium hydrogen sulfate MIM(CH₂)₄SO₃H]HSO₄], a Brønsted acidic ionic liquid, the reaction of aromatic aldehydes with 4-hydroxycoumarin has been investigated. A wide range of aromatic aldehydes easily undergoes condensation with 4-hydroxycoumarin to afford biscoumarins with good purity in excellent yields. However, reaction of 2-hydroxybenzaldehyde with 4-hydroxycoumarin gave, not the corresponding biscoumarin, but a tetracyclic compound, 7-(2-hydroxy-4-oxo-4H-chromen-3-yl)-6H,7H-chromeno4,3-b]chromen-6-one, in high yield.

Keywords:	Biscoumarins 4-Hydroxycoumarin Ionic liquid Unexpected product
本文献已被 ScienceDirect 等数据库收录！