2-Hydroxyethylammonium acetate as a reusable and cost-effective ionic liquid for the efficient synthesis of bis(pyrazolyl)methanes and 2-pyrazolyl-1-nitroalkanes

2012 ◽  
Vol 90 (10) ◽  
pp. 798-804 ◽  
Author(s):  
Sara Sobhani ◽  
Razieh Nasseri ◽  
Moones Honarmand

A new and convenient method for the synthesis of bis(pyrazolyl)methanes by one-pot tandem Knoevenagel–Michael reaction of 3-methyl-1-phenyl-5-pyrazolone with aryl, heteroaryl, or alkyl aldehydes in the presence of 2-hydroxyethylammonium acetate (2-HEAA) as a task-specific ionic liquid is described. This method was also successfully applied for the synthesis of 2-pyrazolyl-1-nitroalkanes by Michael addition of 3-methyl-1-phenyl-5-pyrazolone with β-nitrostyrenes in short reaction times. The present protocol offers several advantages such as using a reusable and cost-effective ionic liquid, an environmentally benign reaction media, being amenable to scale-up and good to high yields of the products.

SynOpen ◽  
2020 ◽  
Vol 04 (04) ◽  
pp. 89-95
Author(s):  
Swapan Majumdar ◽  
Barnali Deb ◽  
Ankita Chakraborty ◽  
Jewel Hossain

AbstractA robust and straightforward protocol has been developed for the synthesis of a diverse array of dimethyl acetal protected benz­imidazole-2-carboxaldehydes by reacting various 2-amino aniline derivatives with methyl 4,4-dimethoxy-3-oxobutanoate using the task-specific­ imidazolium ionic liquid (HBIm·TFA) as a promoter for N-C/C-N annulation processes. The present protocol offers several advantages over existing protocols, such as single-step process, short reaction times, very mild reaction conditions, high yields, ease of purification, recovery and reusability of the catalyst, and scale-up of the reaction.


2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Kobra Nikoofar ◽  
Fatemeh Shahriyari

AbstractA simple, straightforward, and ultrasound-promoted method for the preparation of some highly functionalized tetrahydropyridines reported via pseudo five-component reaction of (hetero)aromatic aldehydes, different anilines, and alkyl acetoacetates in the presence of [N-CH2CO2H-3-pic]+HSO4−, as a novel ionic liquid, in green aqueous medium. The IL was synthesized utilizing simple and easily-handled substrates and characterized by FT-IR, 1H NMR, 13C NMR, GC-MASS, FESEM, EDX, and TGA/DTG techniques. The procedure contains some highlighted aspects which are: (a) performing the MCR in the presence of aqua and sonic waves, as two main important and environmentally benign indexes in green and economic chemistry, (b) high yields of products within short reaction times, (c) convenient work-up procedure, (d) preparing the new IL via simple substrates and procedure.


2012 ◽  
Vol 67 (7) ◽  
pp. 717-724
Author(s):  
Shihua Song ◽  
Xiang Deng ◽  
Zhi Guan ◽  
Yanhong He

A simple method for the synthesis of phthalazinetrione derivatives by a one-pot three-component condensation reaction of phthalhydrazide, 1,3-dicarbonyl compounds and aldehydes catalyzed by the ionic liquid 4-(3-methyl-1-imidazolio)-1-butanesulfonic acid hydrogen sulfate ([BSO3HmIm]HSO4) is reported. Good to excellent yields were obtained in short reaction times in the solvent PEG 600 (polyethylene glycol 600) at 120 °C. The strategy proved to be efficient and environmentally benign. The catalyst/solvent system could easily be recovered and reused for at least 5 times without noticeable loss of activity


2005 ◽  
Vol 2005 (9) ◽  
pp. 600-602 ◽  
Author(s):  
Yu-Ling Li ◽  
Mei-Mei Zhang ◽  
Xiang-Shan Wang ◽  
Da-Qing Shi ◽  
Shu-Jiang Tu ◽  
...  

In this paper the preparation of 3,3,6,6-tetramethyl-9-aryl-1,2,3,4,5,6,7,8,9,10- decahydroacridin-1,8-dione derivatives from aromatic aldehydes, 5,5-dimethyl-1,3- cyclohexanedione and ammonium acetate in ionic liquids [bmim+][BF4-] is described. This new method has the advantages of easier work-up, milder reaction conditions, high yields and an environmentally benign procedure compared with other methods.


2011 ◽  
Vol 65 (4) ◽  
Author(s):  
Hossein Eshghi ◽  
Narges Mirzaie

AbstractPolycondensation reactions of phenols with phthalic anhydride were carried out in the presence of ferric hydrogensulphate under melt conditions. The reactions proceeded in short reaction times by using a catalytic amount of Fe(HSO4)3 and the corresponding fluorescein derivatives were obtained in high yields. The simplicity, scale-up, along with the use of an inexpensive, non-toxic, recyclable catalyst of an environmentally benign nature, are other remarkable features of the procedure. The absorption and emission properties of these fluorescein derivatives were studied.


2012 ◽  
Vol 77 (4) ◽  
pp. 407-413 ◽  
Author(s):  
Khalil Tabatabaeian ◽  
Hannaneh Heidari ◽  
Alireza Khorshidi ◽  
Manouchehr Mamaghani ◽  
Nosrat Mahmoodi

The one-pot domino Knoevenagel-type condensation/Michael reaction of aromatic, heteroaromatic and aliphatic aldehydes with 4-hydroxycoumarin in aqueous media in the presence of ruthenium salt as homogeneous catalyst was investigated. It was found that 5 mol% of RuCl3.nH2O catalyzes biscoumarin synthesis in high yields (70-95%) under optimised, mild, green and environmentally benign reaction conditions in short times (25-35min).


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Ravikumar Nagalapalli ◽  
Satyanarayana Reddy Jaggavarapu ◽  
Venkata Prasad Jalli ◽  
Anand Solomon Kamalakaran ◽  
Gopikrishna Gaddamanugu

Ultrasound promoted mild one-pot multicomponent synthesis of 3,4-dihydropyrano[c]chromenes from 4-hydroxycoumarin, arylaldehydes and malononitrile was achieved in aqueous media. The methodology promises advantages of short reaction times, environmentally benign conditions, high yields, and operational convenience.


2008 ◽  
Vol 2008 (11) ◽  
pp. 642-643 ◽  
Author(s):  
Yi Hu ◽  
Hui Kang ◽  
Bi-Wen Zeng ◽  
Ping Wei ◽  
He Huang

A series of 3-arylidene-1,3-dihydroindol-2-one derivatives were conveniently synthesised by the condensation of aromatic aldehydes with 1,3-dihydroindol-2-one using a Brønsted acidic ionic liquid as a dual solvent-catalyst. This method has the advantages of short reaction times, simple work-up, high yields with high purity, being environmentally benign and the ionic liquid can be reused.


2021 ◽  
Vol 11 (2-S) ◽  
pp. 89-97
Author(s):  
Vishal Mane ◽  
Dhanjay Mane

The [DBN][HSO4] -promoted Knoevenagel condensation followed by cyclization protocol has been developed for the first time by a successive reaction of aldehydes, dimedone and malononitrile to afford 2-Amino-4H-pyrans derivatives in high to excellent yields at room temperature. The synergic couple of microwave and ionic liquid provided the capability to allow a variability of functional groups, short reaction times, easy workup, high yields, recyclability of the catalyst, and solvent-free conditions, thus providing economic and environmental advantages. Keywords: [DBN][HSO4], Environmentally benign, 2-Amino-4H-pyrans, Knoevenagel condensation, Microwave irradiation


2018 ◽  
Vol 73 (5) ◽  
pp. 289-293 ◽  
Author(s):  
Mostafa Karami ◽  
Abdolkarim Zare

AbstractA solvent-free protocol for the production of 1-thioamidoalkyl-2-naphthols via a one-pot multi-component reaction of arylaldehydes with 2-naphthol and thioacetamide using the ionic liquid 1,3-disulfonic acid imidazolium trifluoroacetate ([Dsim][TFA]) is described. Furthermore, a plausible and attractive mechanism based on the dual functionality of the catalyst is proposed. Because of the dual functionality of [Dsim][TFA] (possessing acidic and basic sites), it is found to be generally highly effective, affording the products in high yields and short reaction times under mild conditions. We claim that this is one of the best protocols for the synthesis of 1-thioamidoalkyl-2-naphthols (in terms of yield, temperature, conditions, and/or the reaction time).


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