Facile synthesis of functionalized 6-cyano-2-oxa-7-azabicyclo[4.1.0]hept-3-en-1-yl acetates: a catalyst free approach to access the pyran fused 2-acetoxy-NH-aziridines
Facile synthesis of functionalized 6-cyano-2-oxa-7-azabicyclo[4.1.0]hept-3-en-1-yl acetates: a catalyst free approach to access the pyran fused 2-acetoxy-NH-aziridines
A green one-pot three-component synthesis of tetrahydrobenzo[b]pyran and 3,4-dihydropyrano[c]chromene derivatives using a Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub>–imid–PMA<sup>n</sup> magnetic nanocatalyst under ultrasonic irradiation or reflux conditions
An efficient and environmentallybenign procedure for the synthesis of tetrahydrobenzo[b]pyran and 3,4-dihydropyrano[c]chromene derivatives has been developed by a one-pot three-component reaction of various aldehydes, malononitrile, and dimedone or hydroxycoumarin in the presence of Fe3O4@SiO2–imid–PMAn nanoparticles as magnetic catalysts under ultrasonic irradiation or reflux conditions in water
通过在锅中各种醛,丙二腈,二甲酮或羟基香豆素的一锅三组分反应,开发了一种有效的,对环境无害的合成四氢苯并[ b ]吡喃和3,4-二氢吡喃并[ c ]色烯衍生物的方法。 Fe 3 O 4 @SiO 2-亚胺基-PMA n的存在超声辐射或水中回流条件下,纳米颗粒作为磁性催化剂。该新方法具有显着的优点,例如操作简单,产率高,反应时间短以及无需任何繁琐的后处理或纯化。另外,在水介质中的优异催化性能以及催化剂的易于制备,热稳定性和分离使其成为良好的非均相体系,并且是其他非均相催化剂的有用替代品。同样,该催化剂可以很容易地通过磁场回收并在连续的八个反应循环中重复使用而没有明显的活性损失。
Another application of (NH<sub>4</sub>)<sub>42</sub>[Mo<sup>VI</sup><sub>72</sub>Mo<sup>V</sup><sub>60</sub>O<sub>372</sub>(CH<sub>3</sub>COO)<sub>30</sub>(H<sub>2</sub>O)<sub>72</sub>] as a highly efficient recyclable catalyst for the synthesis of dihydropyrano[3,2-<i>c</i>]chromenes
catalyst for the synthesis of heterocyclic compounds, in this paper, we report another application of this attractive catalyst in the synthesis of 2‐amino‐5‐oxo‐4,5‐dihydropyrano[3,2‐c]chromene‐3‐carbonitriles via a one‐pot three‐component reaction of 4‐hydroxycoumarin, aldehydes and malononitrile. The reactions occur in ethanol–water as solvent at room temperature and the process is operative with
Tertiary amine-bisquaternary ammonium functionalized polyacrylonitrile fiber for catalytic synthesis of pyran-annulated heterocycles
作者:Chima E. Anyaegbu、Haonan Zhang、Jian Xiao、Minli Tao、Ning Ma、Wenqin Zhang
DOI:10.1016/j.reactfunctpolym.2022.105201
日期:2022.3
fiber supported bisquaternary ammoniumsalts with varying interchain quaternaryammonium (QA) to tertiary amine (TA) ratio, counter ions and linker groups were prepared and characterized by TGA, FTIR, XPS, XRD, SEM, EA and water contact angle. The functionalized fibers were used to catalyze three-component reaction (3CR) and tandem deacetalization-3CR for the synthesis of pyrano[4,3-b]pyrans, pyrano[3
制备了具有不同链间季铵 (QA) 与叔胺 (TA) 比例、抗衡离子和连接基团的聚丙烯腈纤维负载双季铵盐,并通过 TGA、FTIR、XPS、XRD、SEM、EA 和水接触角对其进行了表征。功能化纤维用于催化三组分反应(3CR)和串联脱缩醛化-3CR,用于合成吡喃[4,3- b ]吡喃、吡喃[3,2- c ]色烯和吡喃[3,2- c] 喹啉在乙醇-水混合物中。在时间、温度、催化剂用量和溶剂等不同反应条件下,考察了制备的纤维催化剂的催化能力。在最佳条件下,在制备的纤维催化剂中,具有醋酸抗衡离子且链间 QA 与 TA 比为 1:1 的双季铵纤维(PAN BQAc F)表现出最好的催化活性,可连续使用 10 次。催化活性仅略有下降。有趣的是,PAN BQAcF可以有效地催化串联脱缩醛-Knoevenagel反应和相关的新型串联脱缩醛-3CRs,用于合成吡喃环化杂环。在串联脱缩醛化反应中,乙酸根离子在促进质子转移方面发挥着重要作用,这使得
Aliphatic aldehydes in the synthesis of condensed 4-alkyl(cycloalkyl)-2-amino-3-cyano-4H-pyrans
作者:G. V. Klokol、S. G. Krivokolysko、V. D. Dyachenko、V. P. Litvinov
DOI:10.1007/bf02323376
日期:1999.10
Facile synthesis of functionalized 6-cyano-2-oxa-7-azabicyclo[4.1.0]hept-3-en-1-yl acetates: a catalyst free approach to access the pyran fused 2-acetoxy-NH-aziridines
作者:Prasun Mukherjee、Asish R. Das
DOI:10.1039/c5ra24510a
日期:——
Novel pyran fused 2-acetoxy-NH-aziridine scaffold was constructed by reacting the enamine fragment of 4-H-pyrans and spiropyrans using iodobenzene diacetate under catalyst free environment.