A versatile and efficient single‐step route to 3‐cyanocoumarins via Knoevenagel condensation of salicylaldehydes and malononitrile using ZrCl4 as the catalyst (15 mol %) in ionic liquid 1‐(n‐butyl)‐3‐methylimidazolium tetrafluoroborate as reaction medium and catalyst is described. The novel procedure features single step, short reaction time, good yields, and simple workup. J. Heterocyclic Chem., (2011)
Facile, efficient, and eco-friendly synthesis of benzo[b]pyran-2-imines over MgO and transformation to the coumarin derivatives
作者:Hassan Valizadeh、Ashraf Fakhari
DOI:10.1002/jhet.265
日期:2009.11
Room temperature synthesis of benzo[b]pyran‐2‐imine derivatives via the Knoevenagel condensation of malononitrile and cyanoacetates with salicylaldehyde derivativesoverMgO and their transformation to the known coumarins is described. The satisfactory results were obtained with good yields, short reaction time, and simplicity in the experimental procedure. J. Heterocyclic Chem., (2009).
Potassium Triiodide. A New and Efficient Catalyst for Carbon–Carbon Bond Formation in Aqueous Media
作者:Ashim J. Thakur、Dipak Prajapati、Baikuntha J. Gogoi、Jagir S. Sandhu
DOI:10.1246/cl.2003.258
日期:2003.3
Potassiumtriiodide catalyses the condensation of carbonyl compounds with active methylene compounds in aqueous media to afford E olefinic products in high yields.
Application of the polyacrylonitrile fiber as a support for the green heterogeneous base catalyst and supported phase-transfer catalyst
作者:Xian-Lei Shi、Minli Tao、Huikun Lin、Wenqin Zhang
DOI:10.1039/c4ra12069h
日期:——
Highly efficient and recyclable polyethylene polyamine functionalized polyacrylonitrile fiber as the heterogeneous base catalyst and supported phase-transfer catalyst.
Copper-Catalyzed Imino C–N Bond Formation with Aryl Boronic Acids under Aerobic Conditions
作者:A. Kumar、Prashant Mandal
DOI:10.1055/s-0035-1561382
日期:——
A copper-catalyzed, ligand- and base-free C–N cross-coupling reaction of iminochromenes with arylboronicacids in a nontoxic ethanol solvent at room temperature underair is developed. The product yields are found to be good to moderate. The conservation of the sensitive imine functional group implies the mildness of this protocol