Perchloric acid modified-cellulose: a versatile, novel and biodegradable heterogeneous solid acid catalyst for single-pot synthesis of novel bis-pyran annulated heterocyclic scaffolds under solvent-free conditions
作者:Tabassum Khan、Zeba N. Siddiqui
DOI:10.1039/c4nj00529e
日期:——
the synthesis of novel bis-pyran annulated heterocyclic scaffolds (4a–r) using cellulose–perchloric acid (CPA) as an eco-friendly, biodegradable and recyclable catalyst in excellent yields undersolvent-freeconditions. Other remarkable features of this environmentally benign protocol are short reaction time, a wide range of functional group tolerance, use of inexpensive heterogeneouscatalyst, and
Mono- and Bis-2-amino-4H-pyrans: Alum Catalyzed Three- or Pseudo Five-Component Reaction of 4-Hydroxycoumarin, Malononitrile and Aldehydes
作者:Ali Reza Karimi、Cyrus Eslami
DOI:10.2174/157017811794697421
日期:2011.2.1
An efficient method for the three- or pseudofive-componentsynthesis of mono- and bis-2-amino-4H-pyrans in excellent yields using Alum (KAl(SO4)2.12H2O) as recyclable catalyst is described. The present methodology offers several advantages such as excellent yields, simple procedures, shorter reaction times, milder conditions and the catalysts exhibited remarkable reusable activity.
Highly efficient three-component, one-pot synthesis of dihydropyrano[3,2-c]chromene derivatives
作者:Hong-Juan Wang、Jie Lu、Zhan-Hui Zhang
DOI:10.1007/s00706-010-0383-4
日期:2010.10
AbstractAn efficient and convenient method for synthesis of dihydropyrano[3,2-c]chromene derivatives by one-pot, three-component reaction of aldehydes, malononitrile, and 4-hydroxycoumarin in the presence of a catalytic amount of hexamethylenetetramine is reported. A variety of dihydropyrano[3,2-c]chromene derivatives were obtained in high to excellent yields within short times. Graphical abstract
摘要据报道,在催化量的六亚甲基四胺存在下,通过醛,丙二腈和4-羟基香豆素的一锅三组分反应,合成二氢吡喃并[3,2- c ]亚甲基苯衍生物的有效方法。在短时间内以高产率至优异产率获得了多种二氢吡喃并[3,2- c ]亚甲基苯衍生物。 图形概要
Ru(II) complexes bearing tertiary phosphine ligands: a novel and efficient homogeneous catalyst for one-pot synthesis of dihydropyrano[3,2-c]chromene and tetrahydrobenzo[b]pyran derivatives
作者:Khalil Tabatabaeian、Hannaneh Heidari、Manouchehr Mamaghani、Nosrat O. Mahmoodi
DOI:10.1002/aoc.1866
日期:2012.2
A number of ruthenium complexes were prepared and their catalytic activities in three‐component one‐pot condensation of aldehydes, malononitrile and 4‐hydroxycoumarin or dimedone was considered to afford dihydropyrano[3,2‐c]chromenes and tetrahydrobenzo[b]pyranderivatives under optimum reaction conditions. We found that a catalytic amount of RuBr2(PPh3)4 efficiently promotes the reaction in a short