A magnetic nanoparticle supported Ni2+-containing ionic liquid as an efficient nanocatalyst for the synthesis of Hantzsch 1,4-dihydropyridines in a solvent-free dry-system
A facile and efficient synthesis of new 1,4‐dihydropyridine derivatives was reported via Hantzsch three‐component condensation reaction of aldehydes or formylphenylboronic acids, ethyl acetoacetate, and ammonium acetate in the presence of a catalytic amount of triethylamine under solvent‐free conditions. The method described here offers several advantages including high yields, short reaction times
CAN Mediated Mechanochemical Synthesis of Substituted Pyridine Derivatives
作者:Radhika Khanna、Aarti Dalal、Kulbir Kadyan、Ramesh Kumar、Parvin Kumar、Ramesh C. Kamboj
DOI:10.2174/1570178615666180102153707
日期:2018.7.2
A simple, green and cost-effective protocol has been devised for the synthesis of
4-substituted-2,6-dimethyl-3,5-pyridinecarboxylates from Hantzsch-type 1,4-dihydropyridines via
rapid oxidation in excellent yields using 1.5 equivalent of ceric ammonium nitrate within 15 minutes in
solvent-free conditions. The method was able to furnish the products in excellent yields. The products
obtained were characterized by their NMR and melting points data.
Facile Aromatisation of Hantzsch 1,4-Dihydropyridines by Autoxidation in the Presence of <i>P</i>-toluenesulfonic Acid in Acetic Acid
作者:Ding Zhang、Min Sha
DOI:10.3184/174751918x15208600846791
日期:2018.3
A simple protocol to achieve the aromatisation of Hantzsch dihydropyridines in high yield was established using p-toluenesulfonic acid in acetic acid and yields of 90% were obtained at room temperature. With regards to the Hantzsch1,4-dihydropyridines derived from alkyl aldehydes bearing one or more á-hydrogens, dealkylation products were obtained through a proposed autoxidation mechanism.
A series of aza-crown ether ionic liquids supported on magnetic Fe3O4@SiO2 core–shell particles were designed, synthesized and characterized by elemental analysis, TEM, TG and FT-IR. These new aza-crown ether complex cation ionic liquids were utilized as heterogeneous acidic catalysts in Friedel–Crafts alkylation and Hantzsch reaction in good yields under convenient reaction conditions. Moreover, these
设计,合成并通过元素分析,TEM,TG和FT-IR表征了在磁性Fe 3 O 4 @SiO 2核-壳颗粒上负载的一系列氮杂-冠醚离子液体。这些新型的氮杂-冠醚络合物阳离子离子液体在便利的反应条件下,以良好的收率被用作Friedel-Crafts烷基化和Hantzsch反应中的多相酸性催化剂。而且,这些磁性颗粒负载的IL催化剂可以容易地通过外部磁体回收并重复使用五次而没有明显的活性损失。
Synthesis of 1,4-Dihydropyridines Using Ce(SO<sub>4</sub>)<sub>2</sub>-SiO<sub>2</sub>as Catalyst under Solvent-free Conditions
作者:Wen Pei、Qin Wang、Xiaonian Li、Li Sun
DOI:10.1002/cjoc.201090101
日期:2010.1
A facile and efficient one‐pot synthesis of 1,4‐dihydropyridines from aldehyde, 1,3‐dicarbonyl compounds and ammonium acetate in the presence of Ce(SO4)2‐SiO2 at 80°C under solvent‐freeconditions is described. Compared with the classical Hantzsch reaction, this novel method consistently has the advantages of excellent yields and short reaction time.