Graphene oxide–TiO<sub>2</sub> composite: an efficient heterogeneous catalyst for the green synthesis of pyrazoles and pyridines
作者:Shweta Kumari、Amiya Shekhar、Devendra D. Pathak
DOI:10.1039/c5nj03380b
日期:——
GO–TiO2 has been found to be a highly efficient and recyclable heterogeneous catalyst for the synthesis of pyrazoles and pyridines in aqueous medium at room temperature.
GO–TiO2已被发现是一种在室温下在水性介质中合成吡唑和吡啶的高效可回收的非均相催化剂。
Catalytic applications of {[HMIM]C(NO<sub>2</sub>)<sub>3</sub>}: as a nano ionic liquid for the synthesis of pyrazole derivatives under green conditions and a mechanistic investigation with a new approach
作者:Mohammad Ali Zolfigol、Fatemeh Afsharnadery、Saeed Baghery、Sadegh Salehzadeh、Farahnaz Maleki
DOI:10.1039/c5ra16289k
日期:——
the same reaction conditions. The described reactions were in good agreement with the green chemistry disciplines and their major advantages are short reaction times, good yields, ease of separation, recycling and reusability of NIL. A new mechanistic approach was proposed for the final step of the pyrazolessynthesis which was supported by theoretical studies.
研究了1-甲基咪唑三硝基甲烷[HMIM] C(NO 2)3 }作为第一类纳米离子液体(NIL)的催化应用。所描述的NIL在无溶剂和环境条件下于室温下以各种芳香醛,丙二腈和苯肼的三组分缩合反应,以良好至优异的收率有效地测试了5-氨基-吡唑-4-腈衍生物的合成。在下一个研究中,还通过以下方法合成了1,4-二氢吡喃基-[2,3- c ]-吡唑衍生物在相同反应条件下,在NIL的存在下,将多种芳族醛,丙二腈,苯肼和乙酰乙酸乙酯进行四组分缩合。所描述的反应与绿色化学学科非常吻合,它们的主要优点是反应时间短,收率高,NIL易于分离,回收和可重复使用。吡唑合成的最后一步提出了一种新的机制方法,该方法得到了理论研究的支持。
Glucose-coated superparamagnetic nanoparticle-catalysed pyrazole synthesis in water
heterogeneous, superparamagnetic catalyst (Glu.@Fe3O4) was synthesized and characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy and vibrating sample magnetometry. The prepared catalyst was used to achieve a high‐efficiency, low‐cost, eco‐friendly and easy‐to‐handle protocol for synthesizing substituted pyrazole derivatives
合成了绿色,良性,非均质,超顺磁性催化剂(Glu。@ Fe 3 O 4),并使用傅里叶变换红外光谱,X射线衍射,热重分析,扫描电子显微镜和振动样品磁强分析对其进行了表征。制备的催化剂用于从醛,丙二腈和苯肼合成取代吡唑衍生物的高效,低成本,生态友好和易于操作的方案中。该催化剂也用于色烯合成中。涂覆在磁性纳米颗粒上的葡萄糖具有出色的催化活性。该催化剂可以循环使用多达四次,而不会明显降低催化活性。
An environmentally friendlier approach—ionic liquid catalysed, water promoted and grinding induced synthesis of highly functionalised pyrazole derivatives
Grinding induced synthesis of highly functionalised pyrazoles derivatives by use of malanonitrile, phenyl hydrazine and diversified aldehyde. Ionic liquid is used as a catalyst with water, and no by-products form. A high yield is obtained and simple handling are the benefits of the adopted route, and this route fulfils all shades of green chemistry.
MWCNTs‐ZrO
<sub>2</sub>
as a reusable heterogeneous catalyst for the synthesis of
<i>N</i>
‐heterocyclic scaffolds under green reaction medium
作者:Bipasa Halder、Flora Banerjee、Ahindra Nag
DOI:10.1002/aoc.5906
日期:2020.11
scanning electron microscopy, and X‐ray photoelectron spectroscopy analysis. The heterogeneous nanocomposite has been used for one‐potsynthesis of various N‐heterocyclic compounds like pyrazoles, 1,2‐disubstituted benzimidazoles, 2‐arylbenzazoles, and 2,3‐dihydroquinazolin‐4(1H)‐ones under green reaction medium at room temperature. This novel method has several advantages, such as short reaction time, simple