- Mechanistic Studies on the Michael Addition of Amines and Hydrazines to Nitrostyrenes: Nitroalkane Elimination via a Retro-aza-Henry-Type Process
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In this article we report on the mechanistic studies of the Michael addition of amines and hydrazines to nitrostyrenes. Under the present conditions, the corresponding N-alkyl/aryl substituted benzyl imines and N-methyl/phenyl substituted benzyl hydrazones were observed via a retro-aza-Henry-type process. By combining organic synthesis and characterization experiments with computational chemistry calculations, we reveal that this reaction proceeds via a protic solvent-mediated mechanism. Experiments in deuterated methanol CD3OD reveal the synthesis and isolation of the corresponding deuterated intermediated Michael adduct, results that support the proposed slovent-mediated pathway. From the synthetic point of view, the reaction occurs under mild, noncatalytic conditions and can be used as a useful platform to yield the biologically important N-methyl pyrazoles in a one-pot manner, simple starting with the corresponding nitrostyrenes and the methylhydrazine.
- Kallitsakis, Michael G.,Tancini, Peter D.,Dixit, Mudit,Mpourmpakis, Giannis,Lykakis, Ioannis N.
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supporting information
p. 1176 - 1184
(2018/02/09)
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- Synthesis, Characterization and Catalytic Application of MCM 41 Supported Phenanthrolinium Dibromide Catalyst for Aza-Michael Addition Reaction in Aqueous Medium
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Abstract: MCM-41 immobilized phenanthrolinium dibromide (phen-MCM-Br2) was easily prepared and applied as an efficient heterogeneous catalyst for aza-Michael addition of aromatic amines to α,β-unsaturated nitriles and nitro compounds in water. The catalyst was characterized by CHN, TGA, FT-IR, SEM, EDAX, XRD, BET, and TEM. It could be simply recovered and reused several times without significant loss of catalytic activity. Graphical Abstract: [Figure not available: see fulltext.]
- Hosseinzadeh, Rahman,Aghili, Nora,Tajbakhsh, Mahmood
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p. 1194 - 1203
(2016/07/06)
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- Scope and limitations of supramolecular autoregulation
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Recently, our group has reported on the ureidopyrimidinone (UPy) induced buffering of 2,7-diamido-1,8-naphthyridine (NaPy) and used this phenomenon to regulate the catalysis of the Michael addition of 2,4-pentanedione to trans-a-nitrostyrene. We now show that the observed catalytic activity of NaPy is the result of a strong synergy between NaPy and trace amounts of K2CO3, resulting in a more than 100-fold increase in reaction rate compared to the two compounds separately. By keeping the concentration of K2CO3, as well as NaPy, constant, an improved regulation of the catalytic activity is achieved. We show that the catalytic activity can be precisely regulated in a noncovalent manner via the addition of the UPy motif. Finally, different salts and Michael substrates are screened to assess the selectivity of this catalytic couple and to provide a platform for future research in molecular buffering, regulation, and chemical networks.
- Teunissen, Abraham J.P.,Van Der Haas, Roy J.C.,Vekemans, Jef A.J.M.,Palmans, Anja R.A.,Meijer
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supporting information
p. 308 - 314
(2016/04/05)
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- MgO nanoparticles as an efficient and reusable catalyst for aza-Michael reaction
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MgO nanoparticles were prepared by an improved sol-gel technique which appeared to have narrow size distributions. The synthesized magnesium oxide nanoparticles were used as an efficient catalyst in aza-Michael reaction for addition of amines to a series of α,β-unsaturated carbonyl compounds and nitro olefins under solvent-free conditions at room temperature to afford high yields of the β-amino carbonyl and β-nitro amines. The catalyst can be recovered and reused at least five successive runs without loss of activity. Graphical abstract: [Figure not available: see fulltext.]
- Tajbakhsh, Mahmood,Farhang, Maryam,Hosseini, Ali Asghar
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p. 665 - 672
(2014/05/20)
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- Conjugate addition nitro-Mannich reaction of carbon and heteroatom nucleophiles to nitroalkenes
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The conjugate addition nitro-Mannich reactions of ethyl-β-nitroacrylate (1) and β-nitrostyrene (2) with electron rich aromatic nucleophiles, stabilized carbanions, alcohols, amines, thiols, and diphenyl phosphine oxide were investigated. The one pot conju
- Anderson, James C.,Kalogirou, Andreas S.,Tizzard, Graham J.
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p. 9337 - 9351
(2015/03/05)
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- Dolomite (CaMg(CO3)2) as a recyclable natural catalyst in Henry, Knoevenagel, and Michael reactions
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Iranian dolomite (CaMg(CO3)2) which consists of double-layered carbonates with Ca2+ and Mg2+ ions was utilized as a heterogeneous base catalyst in the CC, CN, and CS bond forming reactions via the Henry, Knoevenagel, aza-Michael, and thia-Michael transformations under mild conditions in water. Iranian dolomite has been characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Brunauer Emmett Teller (BET) and XRF chemical analysis, while its basic strength was evaluated by following the Hammett indicators procedure. This water-insoluble natural catalyst demonstrated high activity and was reusable.
- Tamaddon, Fatemeh,Tayefi, Mohammad,Hosseini, Elaheh,Zare, Elham
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- Study on the influence of a sustainable medium for the design of multistep processes: Three-component synthesis of 2-Nitroamines
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An environmentally benign method was developed for the three-component, one-pot synthesis of 2-nitroamines by heating a solution of an aldehyde, an aromatic amine, and a nitroalkane in 20% water–methanol at 60 °C for five hours in the absence of a catalys
- Piscopo, Calogero G.,Sartori, Giovanni,Mayoral, José A.,Lanari, Daniela,Vaccaro, Luigi,Maggi, Raimondo
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p. 2596 - 2600
(2013/12/04)
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- An expeditious, highly efficient, catalyst-free and solvent-free synthesis of nitroamines and nitrosulfides by Michael addition
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A simple, atom economical, fast and highly efficient green protocol has been developed for the synthesis of nitroamines and nitrosulfides by the Michael addition of amines and thiols to nitroolefins by simple mixing or grinding. This catalyst-free and solvent-free green approach provided the addition products in quantitative yield within minutes at room temperature. This procedure does not require any water quenches, solvent separations and purification steps such as recrystallization and column chromatography.
- Choudhary, Garima,Peddinti, Rama Krishna
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p. 276 - 282
(2011/04/17)
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- Zirconium tetrakis(dodecylsulfate) as an efficient and recyclable lewis acid-surfactant-combined catalyzed C-C and C-N bond forming under mild and environmentally benign conditions
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A green catalytic method for C-C and C-N bond forming via Michael addition of aromatic amines and indoles to electron-deficient olefins using Zirconium tetrakis(dodecylsulfate) in water under mild conditions with high yields and selectivity has been developed. The reusability of the catalyst has been successfully examined without any noticeable loss of its catalytic activity.
- Jafarpour, Maasoumeh,Rezaeifard, Abdolreza,Aliabadi, Marzieh
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scheme or table
p. 94 - 99
(2010/04/23)
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- Synthesis of aza-Henry products and enamines in water by Michael addition of amines or thiols to activated unsaturated compounds
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Nitroamines and nitrothiols were synthesized in high yields by the Michael addition of amines and thiols to nitroolefins without using any catalyst. Also, the reaction of amines with dimethylacetylene dicarboxylate (DMAD) in water afforded the corresponding enamines.
- Ziyaei-Halimehjani, Azim,Saidi, Mohammad R.
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p. 1244 - 1248
(2008/09/17)
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- NOVEL COMPOUNDS
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The present invention relates to compounds and derivatives thereof, their synthesis, and their use as glucocorticoid receptor modulators. The compounds of the instant invention are ligands for glucocorticoid receptors and as such may be useful for treatment or prevention of a variety of conditions related to glucocorticoid functioning including rheumatoid arthritis, osteoarthritis, allery, asthma, pneumonia, dermatitis, eczema, psoriasis, lupus, colitis, inflammatory bowel disease, multiple sclerosis, congenital neutropenia, Wegener's granulomatosis, Addison's Disease, Crohn's disease Cushing Syndrome, or as immunosuppressants in organ transplantation.
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Page/Page column 22-23
(2010/02/07)
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- Kinetics and mechanism of the addition of substituted anilines to β-nitrostyrene
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The kinetics of addition of a number of ortho-, meta- and para-substituted anilines to β-nitrostyrene (NS) in acetonitrile have been studied. The reaction is first order with respect to each the aniline and NS. The rate constants were correlated with vari
- Varghese, Bindu,Kothari, Seema,Banerji, Kalyan K.
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p. 1853 - 1871
(2007/10/03)
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