- One-Pot Green Synthesis of 2-Oxo-2H-chromene-3-carbonitriles Using Dual-Frequency Ultrasonication
-
Abstract: A green synthesis of 2-oxo-2H-chromene-3-carbonitriles has been carried out in one step by reacting 2-hydroxybenzaldehydes or 2-hydroxyacetophenones with ethyl cyanoacetate under dual-frequency ultrasonica-tion (ultrasonic bath of 40 KHz and probe of 20 KHz). The compounds were obtained in very high yield, and their structures were confirmed by IR and NMR data.
- Aruna,Kumar, S.,Sharma, S. P.,Vashisht, N.
-
p. 1508 - 1512
(2021/10/26)
-
- Coumarin derivatives act as novel inhibitors of human dipeptidyl peptidase III: Combined in vitro and in silico study
-
Dipeptidyl peptidase III (DPP III), a zinc-dependent exopeptidase, is a member of the metalloproteinase family M49 with distribution detected in almost all forms of life. Although the physiological role of human DPP III (hDPP III) is not yet fully elucida
- ?ubari?, Domagoj,Agi?, Dejan,Be?lo, Drago,Kara?i?, Zrinka,Karna?, Maja,Lisjak, Miroslav,Lon?ari?, Melita,Molnar, Maja,Popovi?, Boris M.,Rastija, Vesna,Tomi?, Sanja
-
-
- Zirconium(IV) oxychloride: A simple and efficient catalyst for the synthesis of chromen-2-one derivatives
-
The present work explores a highly efficient, environmental friendly, green protocol for the synthesis of chromen-2-one derivatives (3a-m) by the condensation of salicylaldehydes with various active methylene compounds using zirconium (IV) oxychloride as catalyst. This is a convenient and rapid method for Knoevenagel condensation and this methodology offers several advantages including shorter reaction time, milder conditions, inexpensive catalyst, simple operational procedure and allowed to achieve the desired products in excellent yields. The structures of all the synthesized compounds were confirmed by spectral data.
- TASQEERUDDIN,ASIRI, YAHYA I.,SHAHEEN
-
p. 2611 - 2616
(2020/10/22)
-
- PhI(OAc)2 mediated an efficient Knoevenagel reaction and their synthetic application for coumarin derivatives
-
A phenyliododiacetate (PhI(OAc)2) mediated an efficient and novel protocol for the Knoevenagel reaction has been successfully accomplished. A base free, simple and straightforward method afforded wide substrate scope and good functional group tolerance, having high yields (80–92%) under environmentally benign and mild reaction conditions.
- Khan, Danish,Mukhtar, Sayeed,Alsharif, Meshari A.,Alahmdi, Mohammed Issa,Ahmed, Naseem
-
supporting information
p. 3183 - 3187
(2017/07/18)
-
- ZIF-8 nanoparticles as an efficient and reusable catalyst for the Knoevenagel synthesis of cyanoacrylates and 3-cyanocoumarins
-
Zeolitic imidazolate framework (ZIF-8) particles with an average size of ca. 355 nm and a specific surface area of 1786 m2.g?1were used as an heterogenous catalyst for the Knoevenagel synthesis of α,β-unsaturated cyanoesters and 3-cy
- Kolmykov, Oleksii,Chebbat, Nassima,Commenge, Jean-Marc,Medjahdi, Ghouti,Schneider, Rapha?l
-
p. 5885 - 5888
(2016/12/14)
-
- The synthesis of coumarin derivatives using choline chloride/zinc chloride as a deep eutectic solvent
-
In this work, choline chloride/zinc chloride was employed as a deep eutectic solvent (DES) in the green synthesis of coumarin derivatives using Knoevenagel condensation. Coumarins are important organic structures with useful application in various fields.
- Keshavarzipour, Fariba,Tavakol, Hossein
-
p. 149 - 153
(2016/01/09)
-
- A cost-effective and green aqueous synthesis of 3-substituted coumarins catalyzed by potassium phthalimide
-
An efficient procedure for the synthesis of various 2-imino-2H-chromene-3-carbonitriles, 2-oxo- 2H-chromene-3-carbonitriles as well as 2-oxo-2H-chromene-3-carboxylic acids is reported. It has been found that potassium phthalimide (PPI) catalyse the Knoevenagel condensation reaction of salicylaldehydes and activated β- dicarbonyl compounds efficiently under aqueous conditions at room temperature. This approach provides many merits such as high yields of products, clean, simple work-up, waste free, mild reaction conditions, commercially available organocatalyst, and the use of water as environmentally benign solvent.
- Kiyani, Hamzeh,Daroonkala, Masoumeh Darzi
-
p. 449 - 456
(2015/10/19)
-
- Iodine-mediated one-pot synthesis of 3-cyanocoumarins and 3-cyano-4-methylcoumarins
-
2-Hydroxybenzaldehydes 1a-e on reaction with malononitrile (2) in the presence of iodine as catalyst give 3-cyanocoumarins 3a-e in one step under thermal heating as well as under microwave irradiation. The latter conditions are much more efficient in terms of time (2-5 min) and yield as compared to the thermal conditions (2-2.5 h). Following a similar procedure, 3-cyano-4-methylcoumarins 3f-i were also prepared by the reaction of 2-hydroxyacetophenones 1f-i with 2.
- Sharma, Dinesh,Makrandi, Jagdish K.
-
p. 527 - 531
(2014/06/10)
-
- FeCl3-catalyzed cascade reaction: An efficient approach to functionalized coumarin derivatives
-
An efficient and environmentally benign synthesis of 3-substituted or 3,4-disubstituted coumarins was accomplished via iron(III) chloride-catalyzed cascade reactions of salicylaldehydes and activated methylene compounds. The reaction preceded cleanly under mild reaction conditions to provide the desired coumarin derivatives in good to excellent yields.
- He, Xinwei,Yan, Zhenglei,Hu, Xiaoqian,Zuo, Yin,Jiang, Chang,Jin, Lei,Shang, Yongjia
-
supporting information
p. 1507 - 1514
(2014/05/20)
-
- An efficient one-pot synthesis of coumarins mediated by propylphosphonic anhydride (T3P) via the Perkin condensation
-
An efficient one-pot synthesis of coumarins mediated by T3P, a mild and low toxic peptide coupling agent, via the Perkin condensation has been demonstrated.
- Augustine, John Kallikat,Bombrun, Agnes,Ramappa, Balakrishna,Boodappa, Chandrakantha
-
experimental part
p. 4422 - 4425
(2012/09/25)
-
- ZrCl4/[bmim]BF4-catalyzed condensation of salicylaldehydes and malononitrile: Single-step synthesis of 3-cyanocoumarin derivatives
-
Figure represented. A versatile and efficient single-step route to 3-cyanocoumarins via Knoevenagel condensation of salicylaldehydes and malononitrile using ZrCl4 as the catalyst (15 mol %) in ionic liquid 1-(n-butyl)-3-methylimidazolium tetrafluoroborate as reaction medium and catalyst is described. The novel procedure features single step, short reaction time, good yields, and simple workup.
- Valizadeh, Hassan,Mahmoodian, Manzar,Gholipour, Hamid
-
experimental part
p. 799 - 802
(2011/09/16)
-
- The condensation of salicylaldehydes and malononitrile revisited: Synthesis of new dimeric chromene derivatives
-
(Chemical Equation Presented) The reaction of salicylic aldehydes with malononitrile was reinvestigated, and the reaction pathway was followed by 1H NMR spectroscopy. A delicate control of the experimental conditions allowed the synthesis of 2-imino-2H-chromene-3-carbonitriles 1, (2-amino-3-cyano-4H-chromen-4-yl)malononitriles 2, 4-amino-5-imino-2,7- dimethoxy-5H-chromeno[3,4-c]pyridine-1-carbonitrile 12, and (4,5-diamino-1- cyano-1,10b-dihydro-2H-chromeno[3,4-c]pyridin-2-ylidene)malononitrile 13. Two novel 2-iminochromene dimers, with structures 8 and 9, were isolated and fully characterized. The activity of compound 8a on Aspergillus spp. growth and on ochratoxin A production was evaluated. The results of the bioassays indicate that compound 8a, applied at concentrations of 2 mM, totally inhibited the growth of the fungi tested. Ochratoxin A production by Aspergillus alliaceus was reduced by about 93% with a 200 μM solution of this compound. A moderate inhibitory effect was observed for the analogous structure 8b, and no inhibition was registered for compounds 2 and 1, used as synthetic precursors of the dimeric species 8.
- Costa, Marta,Areias, Filipe,Abrunhosa, Luis,Venancio, Armando,Proenca, Fernanda
-
p. 1954 - 1962
(2008/09/19)
-
- Conversion of coumarins accompanied by opening and recyclization of the lactone ring. 1. Study of the reaction of 3-ethoxycarbonyl(3-acyl)coumarins with cyanoacetylhydrazine and its derivatives
-
A stepwise sequence for the interaction of 3-ethoxycarbonyl(acyl)coumarins with cyanoacetylhydrazine, its N-acetyl and N-isopropylidene derivatives, leading to the formation of 3-cyanocoumarins, is proposed and demonstrated. It was established that the 3-cyanocoumarins formed are also able to participate in further conversions by a type of Michael reaction.
- Nemeryuk,Dimitrova,Anisimova,Sedov,Solov'eva,Traven
-
p. 1454 - 1465
(2007/10/03)
-
- Penicillins and their antibacterial use
-
The invention provides novel penicillins and cephalosporins of formula I, STR1 methods for their production and their anti-bacterial use.
- -
-
-