A new silica based substituted piperidine derivative catalyzed expeditious room temperature synthesis of homo and hetero bis-Knoevenagel condensation products
作者:Chhanda Mukhopadhyay、Suman Ray
DOI:10.1016/j.catcom.2011.05.033
日期:2011.9
A new silica based piperidine derivative has been designed, synthesized and characterized by solid state carbon 13 CP MAS NMR, BET surface area analysis, IR, TGA studies, elemental analysis and pH experiment. This has been efficiently utilized as a recyclable catalyst for both homo and hetero bis-Knoevenagel condensation products in aqueous-ethanol. This is the first report of the synthesis of hetero
通过固态碳13 CP MAS NMR,BET表面积分析,IR,TGA研究,元素分析和pH实验,设计,合成和表征了一种新的基于二氧化硅的哌啶衍生物。它已被有效地用作乙醇水溶液中均双和杂双-Knoevenagel缩合产物的可回收催化剂。这是我们设计的催化剂合成杂双-Knoevenagel缩合产物的第一份报告。
Cascade Synthesis of 2-Cyanoacrylamides through Deacetalization and/or Knoevenagel Condensation followed by Selective Monohydration of Acetals and Aldehydes over Solid Acid Ferrites
作者:Sumit B. Kamble、Chandrashekhar V. Rode
DOI:10.1002/cctc.201600426
日期:2016.8.22
involving deacetalization and/or Knoevenagel condensation followed by selective monohydration of nitriles starting from acetals (5) and aldehydes (2) with malononitrile (3). A series of aldehydes, dimethyl and diethyl acetals, along with some heterocyclic aldehydes were successfully transformed to 2‐cyanoacrylamides with >95 % yields. TEM images confirmed the coating of the PVP over nanosized Fe3O4
提出了一种新的生物活性2-氰基丙烯酰胺级联合成的方案(1)。该反应在回流条件下,在AcOH-H 2 O介质中,通过一种新型的可磁性回收的固体酸复合物进行,该复合物是氧化铁,聚(乙烯基吡咯烷酮)和磷钨酸(Fe 3 O 4 / PVP-PWA)。通过单中心布朗斯台德酸催化的级联反应(包括脱缩醛和/或Knoevenagel缩合反应,然后由乙缩醛(5)和醛(2)与丙二腈(3)选择性地单水合腈),可以促进这种转化。)。一系列醛,二甲基和二乙基乙缩醛以及一些杂环醛已成功转化为2-氰基丙烯酰胺,收率> 95%。TEM图像证实了PVP在纳米Fe 3 O 4上的涂层。NOESY实验证明了2-苄叉基丙二腈(4)立体选择性单水合为E异构体。由于使用了缩醛和醛,因此该催化剂具有磁性,因此可以有效地循环使用七次。