619-80-7Relevant academic research and scientific papers
Effect of cocatalysts on the reaction of 4-nitrobenzoic acid with ammonia catalyzed by boric acid
Shteinberg
, p. 1282 - 1285 (2006)
The effect of cocatalysts on the reaction of 4-nitrobenzoic acid with ammonia catalyzed by boric acid was studied.
Catalysis of the reaction between 4-nitrobenzoic acid and ammonia by boric acid + polyehylene glycol-400
Shteinberg
, p. 1715 - 1717 (2005)
Solvent effect on the synthesis of 4-nitrobenzamide by the reaction of 4-nitrobenzoic acid with ammonia in the presence of the catalytic system constituted by boric acid and polyethylene glycol-400 was studied.
A study of the kinetics and mechanism of amidation of 4-nitrobenzoic acid with ammonia, catalyzed by boric acid in the presence of polyethylene glycol PEG-400
Shteinberg
, p. 815 - 819 (2011)
Kinetics of the reaction of 4-nitrobenzoic acid with ammonia, catalyzed by the system constituted by boric acid and PEG-400 poly(ethylene glycol), was studied. A catalysis mechanism was suggested, which consists in original synthesis of incomplete polyethylene glycol borate esters, formation on their basis of 4-nitrobenzoic acid borate esters, and their further amidation with ammonia.
New synthesis of 4-nintrobenzamide
Shteinberg
, p. 972 - 974 (2003)
The reaction of 4-nitrobenzoic acid with ammonia in the presence of various catalysts was studied. Tetrabutoxytitanium and boric acid with addition of PEG-400 favor formation of 4-nitrobenzamide in a high yield. The amidation occurs in the temperature range from 160 to 185°C in trichlorobenzene and in a mixture of trichlorobenzene with o-xylene. Neither PEG-400 nor the above catalysts in the absence of PEG-400 do not catalyze the reaction.
Green and efficient Beckmann rearrangement by Cu(II) contained nano-silica triazine based dendrimer in water
Bahreininejad, Mohammad Hasan,Moeinpour, Farid
, p. 893 - 901 (2021/01/12)
In this research, a Cu(II) contained nano-silica triazine based dendrimer was prepared, characterized, and utilized as a retrievable catalytic system (Cu(II)-TrDen@nSiO2) for green formation of primary amides in water at room temperature. The structure of nanoparticles was fully characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetry analysis (TGA). The results revealed that the nanoparticles have spherical morphology and an average size of around 40 nm. The analysis also illustrated that the copper nanoparticles had been successfully loaded on the nitrogen-rich dendritic structure with a uniform distribution. The inductively coupled plasma analysis showed that about 0.67 mmol/g of Cu was loaded on the Cu(II)-TrDen@nSiO2 support. Mild reaction conditions, excellent yields, environment-friendly synthesis, and easily prepared starting materials are the key features of the present method. The catalyst is easily removed from the reaction media using a simple filtration and can be re-used at least five times without any considerable loss of its catalytic activity.
Process Development of the Copper(II)-Catalyzed Dehydration of a Chiral Aldoxime and Rational Selection of the Co-Substrate
Gr?ger, Harald,Nonnhoff, Jannis
, (2021/12/14)
The access towards chiral nitriles remains crucial in the synthesis of several pharmaceuticals. One approach is based on metal-catalyzed dehydration of chiral aldoximes, which are generated from chiral pool-derived aldehydes as substrates, and the use of a cheap and readily available nitrile as co-substrate and water acceptor. Dehydration of N-acyl α-amino aldoximes such as N-Boc-l-prolinal oxime catalyzed by copper(II) acetate provides access to the corresponding N-acyl α-amino nitriles, which are substructures of the pharmaceuticals Vildagliptin and Saxagliptin. In this work, a detailed investigation of the formation of the amide as a by-product at higher substrate loadings is performed. The amide formation depends on the electronic properties of the nitrile co-substrate. We could identify an acceptor nitrile which completely suppressed amide formation at high substrate loadings of 0.5 m even when being used with only 2 equivalents. In detail, utilization of trichloroacetonitrile as such an acceptor nitrile enabled the synthesis of N-Boc-cyanopyrrolidine in a high yield of 92 % and with full retention of the absolute configuration.
Visible light-mediated synthesis of amides from carboxylic acids and amine-boranes
Chen, Xuenian,Kang, Jia-Xin,Ma, Yan-Na,Miao, Yu-Qi
supporting information, p. 3595 - 3599 (2021/06/06)
Here, a photocatalytic deoxygenative amidation protocol using readily available amine-boranes and carboxylic acids is described. This approach features mild conditions, moderate-to-good yields, easy scale-up, and up to 62 examples of functionalized amides with diverse substituents. The synthetic robustness of this method was also demonstrated by its application in the late-stage functionalization of several pharmaceutical molecules.
Manganese-Pincer-Catalyzed Nitrile Hydration, α-Deuteration, and α-Deuterated Amide Formation via Metal Ligand Cooperation
Ben-David, Yehoshoa,Diskin-Posner, Yael,Kar, Sayan,Milstein, David,Zhou, Quan-Quan,Zou, You-Quan
, p. 10239 - 10245 (2021/08/24)
A simple and efficient system for the hydration and α-deuteration of nitriles to form amides, α-deuterated nitriles, and α-deuterated amides catalyzed by a single pincer complex of the earth-abundant manganese capable of metal-ligand cooperation is reported. The reaction is selective and tolerates a wide range of functional groups, giving the corresponding amides in moderate to good yields. Changing the solvent from tert-butanol to toluene and using D2O results in formation of α-deuterated nitriles in high selectivity. Moreover, α-deuterated amides can be obtained in one step directly from nitriles and D2O in THF. Preliminary mechanistic studies suggest the transformations contributing toward activation of the nitriles via a metal-ligand cooperative pathway, generating the manganese ketimido and enamido pincer complexes as the key intermediates for further transformations.
Ru(ii)- And Ru(iv)-dmso complexes catalyze efficient and selective aqueous-phase nitrile hydration reactions under mild conditions
Dubey, Santosh Kumar,Kaur, Gurmeet,Rath, Nigam P.,Trivedi, Manoj
, p. 17339 - 17346 (2021/10/08)
New water-soluble ruthenium(ii)- and ruthenium(iv)-dmso complexes [RuCl2(dmso)2(NH3)(CH3CN)] (1), [RuCl2(dmso)3(CH3CN)] (2), and [RuCl2(dmso)3(NH3)]·PF6·Cl (3) have been synthesized and characterized using elemental analyses, IR, 1H and 31P NMR, and electronic absorption spectroscopy. The molecular structures of complexes 1-3 were determined crystallographically. The reactivity of complexes 1-3 has been tested for aqueous-phase nitrile hydration at 60 °C in air, and good efficiency and selectivity are shown for the corresponding amide derivatives. Best performance is achieved with complex 3. Amide conversions of 56-99% were obtained with a variety of aromatic, alkyl, and vinyl nitriles. The reaction tolerated hydroxyl, nitro, bromo, formyl, pyridyl, benzyl, alkyl, and olefinic functional groups. Amides were isolated by simple decantation from the aqueous-phase catalyst. A catalyst loading down to 0.0001 mol% was examined and turnover numbers as high as 990?000 were observed. The catalyst was stable for weeks in solution and could be reused more than seven times without significant loss in catalytic activity. The gram-scale reaction was also performed to produce the desired product in high yields. This journal is
Activated Mont K10-Carbon supported Fe2O3: A versatile catalyst for hydration of nitriles to amides and reduction of nitro compounds to amines in aqueous media
Rahman, Taskia,Borah, Geetika,Gogoi, Pradip K
, (2021/03/14)
The iron oxide was successfully supported on activated clay/carbon through an experimentally viable protocol for both hydrations of nitrile to amide and reduction of nitro compounds to amines. The as-prepared catalyst has been extensively characterised by XPS, SEM-EDX, TEM, TGA, BET surface area measurements and powdered X-ray diffraction (PXRD). A wide variety of substrates could be converted to the desired products with good to excellent yields by using water as a green solvent for both the reactions. The catalyst was recyclable and reusable up to six consecutive cycles without compromising its catalytic proficiency. Graphical abstract: Activated Mont K10 carbon-supported Fe2O3 is a very efficient and versatile heterogeneous catalytic system for hydration of nitriles to amides and reduction of nitro compounds to amines and can be reused up to six consecutive cycles without significant loss in catalytic activity.[Figure not available: see fulltext.].
