DBU: a highly efficient catalyst for one-pot synthesis of substituted 3,4-dihydropyrano[3,2-c]chromenes, dihydropyrano[4,3-b]pyranes, 2-amino-4H-benzo[h]chromenes and 2-amino-4H benzo[g]chromenes in aqueous medium
作者:Jitender M. Khurana、Bhaskara Nand、Pooja Saluja
DOI:10.1016/j.tet.2010.05.082
日期:2010.7
We have reported DBU catalyzedone-potsynthesis of 3,4-dihydropyrano[3,2-c]chromenes, dihydropyrano[4,3-b]pyranes, 2-amino-4H-benzo[h]chromenes and 2-amino-4H-benzo[g]chromenes from aldehydes, active methylene compounds malononitrile/ethyl cyanocacetate, and 4-hydroxycoumarin/4-hydroxy-6-methylpyrone/1-naphthol/2-hydroxynaphthalene-1,4-dione in water under reflux. The attractive features of this process
我们已经报道了DBU催化一锅合成3,4-二氢吡喃并[3,2- c ]苯并二氢吡喃并[4,3- b ]吡喃,2-氨基-4 H-苯并[ h ]苯并二胺回流下得自醛,活性亚甲基化合物丙二腈/氰基乙酸乙酯和4-羟基香豆素/ 4-羟基-6-甲基吡喃酮/ 1-萘酚/ 2-羟基萘-1,4-二酮的-4 H-苯并[ g ]色酮。该方法的吸引人的特征是温和的反应条件,反应介质的可重复使用性,较短的反应时间,易于分离的产物以及优异的产率。
A synergetic role of Aegle marmelos fruit ash in the synthesis of biscoumarins and 2-amino-4H-chromenes
作者:Rupesh C. Patil、Sachinkumar K. Shinde、Uttam P. Patil、Appasaheb T. Birajdar、Suresh S. Patil
DOI:10.1007/s11164-020-04367-6
日期:2021.4
Abstract A dry rind of Aegle marmelos (bael) fruit ash as a synergetic alternative material to an expensive, toxic and corrosive catalysts for the synthesis of biscoumarins and 2-amino-4H-chromenes at ambient temperature in water is reported. The spectroscopic evidence from EDX, FTIR, XRD and SEM analysis of bael fruit ash supports the presence of metal oxides, carbonates and hydroxides which are intensely
Tris-hydroxymethylaminomethane (THAM): a novel organocatalyst for a environmentally benign synthesis of medicinally important tetrahydrobenzo[b]pyrans and pyran-annulated heterocycles
作者:Kapil S. Pandit、Pramod V. Chavan、Uday V. Desai、Makarand A. Kulkarni、Prakash P. Wadgaonkar
DOI:10.1039/c4nj02346c
日期:——
A simple, efficient and environmentally benign protocol has been developed for the one-pot, multicomponent synthesis of medicinallyimportant tetrahydrobenzo[b]pyrans and pyran-annulated heterocycles using a commercially available, inexpensive, non-toxic, and biodegradable tris-hydroxymethylaminomethane (THAM) as a novel organocatalyst. Ambient reaction conditions, wide scope, avoidance of conventional
已经开发了一种简单,有效且对环境无害的方案,用于使用市售,廉价,无毒且可生物降解的三羟甲基甲基甲烷(THAM)一锅,多组分合成重要的药用四氢苯并[ b ]吡喃和吡喃环杂环)作为新型有机催化剂。环境反应条件,宽范围,避免常规分离以及纯化技术以及催化剂连续五次运行的可重复使用性提高了该多组分反应规程歧管的实用性。
Synthesis of new low-viscous sulfonic acid-functionalized ionic liquid and its application as a Brönsted liquid acid catalyst for the one-pot mechanosynthesis of 4H-pyrans through the ball milling process
作者:Nader Ghaffari Khaligh、Taraneh Mihankhah、Mohd Rafie Johan
DOI:10.1016/j.molliq.2019.01.024
日期:2019.3
solubility in some common solvents. The catalytic activity of new SAIL was demonstrated for the one-pot mechanosynthesis of pyrano[4,3-b]pyrans, dihydropyrano[3,2-c]chromene and tetrahydrobenzo[b]pyrans using planetary ball mill undersolvent-freeconditions. This current mechanosynthesis methodology for the synthesis of 4H-pyran-annulated heterocyclic scaffolds displays a combination of the synthetic virtues
在本研究中,一种新的低粘度磺酸官能化离子液体(SAIL)即。合成了4,4'-三亚甲基-N,N'-磺酸-二哌啶鎓氯化物,并用FTIR,1D和2D NMR以及质谱进行了表征。然后,确定了新的SAIL的一些特性,包括pH,粘度,密度和在某些常用溶剂中的溶解度。在无溶剂条件下,使用行星式球磨机证明了新SAIL对吡喃并[4,3- b ]吡喃,二氢吡喃并[3,2- c ]色烯和四氢苯并[ b ]吡喃的一锅机械合成具有催化活性。目前用于合成4 H的机械合成方法-吡喃环化的杂环支架结合了常规多组分反应的合成优点,生态效益和简单的机械催化方法的便利性。新的SAIL易于回收利用,可以重复使用多次,而不会造成严重的活动损失。
Nano-Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>-supported boron sulfonic acid as a novel magnetically heterogeneous catalyst for the synthesis of pyrano coumarins
magnetically heterogeneouscatalyst based on the immobilization of boron sulfonicacid onto Fe3O4@SiO2 nanoparticles (Fe3O4@SiO2–BSA) is reported. Fe3O4@SiO2–BSA was characterized via FT-IR, X-ray diffraction patterns (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and vibrating sample magnetometer (VSM) analysis. The performance ability of this catalyst including
在这项研究中,报道了一种基于硼磺酸固定在Fe 3 O 4 @SiO 2纳米颗粒(Fe 3 O 4 @SiO 2 -BSA)上的新型磁性非均相催化剂。Fe 3 O 4 @SiO 2 –BSA通过FT-IR,X射线衍射图(XRD),扫描电子显微镜(SEM),能量色散X射线光谱(EDS)和振动样品磁力计(VSM)分析。在无溶剂条件下以高收率评估了该催化剂包括酸位点的性能,以合成吡喃香豆素。催化剂的热稳定性及其易于被磁场分离,使该催化剂成为良好的多相体系,并且是其他多相催化剂的有用替代品。