sample magnetometer (VSM) analyses. This catalyst is outstanding to prepare l‐(4‐phenyl)‐2,4‐dihydropyrano[2,3‐c] pyrazole derivatives in aqueous media due to the open metal sites, high and steady proton conductivity in the zirconium‐MOF, MIP‐202(Zr), and MOF and also due to Brønsted acid properties of tungstic acid. This acidic catalyst can easily be extracted by an outward magnetic field after completion
一种基于钨酸固定到新设计的坚固,经济高效,绿色和可扩展的锆-L-天冬氨酸氨基酸金属-有机骨架(MOF)接枝的L-(+)-酒石酸稳定磁铁矿的新型磁性纳米催化剂纳米粒子(Fe 3 O 4/ tart-NPs)是通过两种连续的溶剂热(水)-热方法合成的。该催化剂的特征在于傅立叶变换红外(FT-IR),能量色散X射线能谱(EDS),X射线衍射(XRD),场发射扫描电子显微镜(FESEM),Brunauer-Emmett-Teller( BET),Barrett-Joyner-Halenda(BJH),ζ电位,热重分析-差热分析(TGA-DTA)和振动样品磁力计(VSM)分析。该催化剂非常适合在水性介质中制备l-(4-苯基)-2,4-二氢吡喃[2,3-c]吡唑衍生物,这是因为锆-MOF,MIP中具有开放的金属位点,高且稳定的质子传导性‐202(Zr)和MOF,也归因于钨酸的布朗斯台德酸性质。反应
Sugarcane Bagasse Ash-Based Silica-Supported Boric Acid (SBA-SiO2-H3BO3): A Versatile and Reusable Catalyst for the Synthesis of 1,4Dihydropyrano[2,3c]pyrazole Derivatives
作者:A. K. Pandey、A. Kumar、S. C. Shrivastava
DOI:10.1134/s1070428021040229
日期:2021.4
one-pot four-component reaction of various substituted benzaldehydes, hydrazinehydrate or phenylhydrazine, ethyl acetoacetate, and malononitrile in aqueous medium in the presence of sugarcane bagasse ash-based silica-supported boric acid (SBA-SiO2-H3BO3) as a solid acid catalyst. The advantages of this methodology are the use of cost-effective and nontoxic catalyst, short reaction time, operational simplicity
摘要 一个简单的,绿色的,高效的协议已被开发用于生物活性1,4dihydropyrano [2,3的合成Ç ]经由各种取代的苯甲醛的一锅四组分反应的吡唑衍生物,水合肼或苯肼,乙酰乙酸乙酯,和在甘蔗渣灰分基二氧化硅负载的硼酸(SBA-SiO 2 -H 3 BO 3)作为固体酸催化剂的存在下,在水性介质中制备丙二腈。这种方法的优点是使用经济高效且无毒的催化剂,反应时间短,操作简便,产率高(90-95%),二氧化硅来源的可用性和绿色方案。
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 Substituted Pyranopyrazoles under Neat Conditions via a Multicomponent Reaction
作者:Boreddy Reddy、Arasampattu Nagarajan
DOI:10.1055/s-0029-1217526
日期:2009.7
A simple and efficient synthesis of pyranopyrazoles in good yields via a four-component reaction between an aromatic aldehyde, hydrazine hydrate, ethyl acetoacetate and malononitrile under neat conditions is described.
Fast synthesis of pyrano[2,3-c]pyrazoles: strong effect of Brönsted and Lewis acidic ionic liquids
作者:Abdol R. Hajipour、Morteza Karimzadeh、Hamed Tavallaei
DOI:10.1007/s13738-014-0561-0
日期:2015.6
approach, four-component synthesis of some pyrano[2,3-c]pyrazoles by [ChCl][ZnCl2]2 and [H-NMP]HSO4 as inexpensive and recyclable acidic ionicliquids were investigated. Excellent yields of products were obtained using both environmentally friendly safe ionicliquids. A comparative study of [ChCl][ZnCl2]2 as Lewis acidic ionicliquid and [H-NMP]HSO4 as Brönsted acidic ionicliquid was also carried out