28533-43-9Relevant academic research and scientific papers
An Environmentally Benign, Catalyst-Free N?C Bond Cleavage/Formation of Primary, Secondary, and Tertiary Unactivated Amides
Kumar, Vishal,Dhawan, Sanjeev,Girase, Pankaj Sanjay,Singh, Parvesh,Karpoormath, Rajshekhar
, p. 5627 - 5639 (2021/11/11)
Herein, we report an operationally simple, cheap, and catalyst-free method for the transamidation of a diverse range of unactivated amides furnishing the desired products in excellent yields. This protocol is environmentally friendly and operates under extremely mild conditions without using any promoter or additives. Significantly, this strategy has been implied in the chemoselective synthesis of a pharmaceutical molecule, paracetamol, on a gram-scale with excellent yield. We anticipate that this universally applicable strategy will be of great interest in drug discovery, biochemistry, and organic synthesis.
Design, synthesis, antibacterial, and antitumor activity of linear polyisocyanide quaternary ammonium salts with different structures and chain lengths
Fu, Shuang,Hou, Peng,Liu, Jun,Liu, Lijia,Zhang, Hongguang
, (2021/09/28)
The development of organic polymer materials for disinfection and sterilization is thought of as one of the most promising avenues to solve the growth and spread of harmful microorgan-isms. Here, a series of linear polyisocyanide quaternary ammonium salts (L-PQASs) with different structures and chain lengths were designed and synthesized by polymerization of phenyl isocyanide monomer containing a 4-chloro-1-butyl side chain followed by quaternary amination salinization. The resultant compounds were characterized by1H NMR and FT-IR. The antibacterial activity of L-PQASs with different structures and chain lengths against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was evaluated by determining the minimum inhibitory concentrations (MICs). The L-POcQAS-M50 has the strongest antimicrobial activity with MICs of 27 μg/mL against E. coli and 32 μg/mL against S. aureus. When the L-PQASs had the same polymerization degree, the order of the antibacterial activity of the L-PQASs was L-POcQAS-Mn > L-PBuQAS-Mn > L-PBnQAS-Mn > L-PDBQAS-Mn (linear, polyisocyanide quaternary ammonium salt, monomer, n = 50,100). However, when L-PQASs had the same side chain, the antibacterial activity reduced with the increase of the molecular weight of the main chain. These results demonstrated that the antibacterial activity of L-PQASs was dependent on the structure of the main chain and the length of the side chain. In addition, we also found that the L-POcQAS-M50 had a significant killing effect on MK-28 gastric cancer cells.
HCl-mediated transamidation of unactivated formamides using aromatic amines in aqueous media
Dhawan, Sanjeev,Girase, Pankaj Sanjay,Kumar, Vishal,Karpoormath, Rajshekhar
, p. 3729 - 3739 (2021/10/14)
We report transamidation protocol to synthesize a range of secondary and tertiary amides from weakly nucleophilic aromatic and hetero-aryl amines with low reactive formamide derivatives, utilizing hydrochloric acid as catalyst. This current acid mediated strategy is beneficial because it eliminates the need for a metal catalyst, promoter or additives in the reaction, simplifies isolation and purification. Notably, this approach conventionally used to synthesize molecules on gram scales with excellent yields and a high tolerance for functional groups.
Palladium supported on MRGO@CoAl-LDH catalyzed reductive carbonylation of nitroarenes and carbonylative Suzuki coupling reactions using formic acid as liquid CO and H2 source
Jadidi Nejad, Masoumeh,Heydari, Akbar
, (2021/07/17)
In the present study, a heterogeneous palladium catalyst system, Pd nanoparticles supported on MRGO@CoAl-LDH, was synthesized and employed in reductive carbonylation of nitroarenes and carbonylative Suzuki coupling reactions using formic acid as CO and H2 source. The as-obtained heterogeneous catalyst was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDAX), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM). The nanocatalyst was reused for 5 cycles with a negligible reduction in the yield of products. All reactions were carried out with high yields and under suitable and safe conditions. Also, we have successfully applied formic acid as a good and safe alternative to CO and H2 gases.
Chiral diolefin rhodium metal catalyst as well as preparation method and application thereof
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Paragraph 0099-0102; 0105-0107, (2020/11/02)
The invention relates to a chiral diene rhodium metal catalyst and a preparation method and application thereof and belongs to the field of catalysts. The preparation method includes: dropwisely adding dimethyl aluminum chloride solution into (-)-alpha-ph
Effective and selective direct aminoformylation of nitroarenes utilizing palladium nanoparticles assisted by fibrous-structured silica nanospheres
Jaseer, E. A.,Qureshi, Ziyauddin S.
, (2020/07/09)
Abstract: Palladium nanoparticles (~ 1–3?nm, 0.4?wtpercent Pd) were uniformly distributed over the surface of fibrous silica nanospheres (KCC-1) modified via aminopropyltriethoxysilane using a fast and cost-effective palladium (II) chloride reduction process. The Pd nanoparticles (Pd NPs) distribution over the ensuing catalyst Pd/KCC-1-NH2 showed much more uniform distribution, and smaller size compared with the tedious hydrothermal reduction method. The morphological, chemical, and size analyses of Pd/KCC-1-NH2 by BET, UV–Vis spectra, XRD, HR-TEM, EDS and XPS analysis revealed that the succeeding material consist of a distinct fibrous silica nanospheres support adorn with Pd NPs. The resultant nanocatalyst was tested for the one-step reductive aminoformylation of aromatic nitro compounds using formic acid. A wide range of substituted nitroarenes including electron withdrawing, releasing, sterically hindered and multifunctional groups have been converted to corresponding aryl formamide in quantitative yields (yields up to 98percent) at moderate temperature (70?°C). Optimization study has proved that the 6 equivalent of formic acid is required and toluene was found to be the better solvent. The established practice is beneficial due to the use of formic acid as H2 source and formylating agent, easiness in handling of the catalyst and simple workup procedure with efficient catalyst reusability. Graphic abstract: [Figure not available: see fulltext.].
A green, efficient, and rapid procedure for the hydrogenation of nitroarenes to formanilides in water
Wang, Yingying,Zhan, Zhajun,Zhou, Yang,Lei, Min,Hu, Lihong
, p. 527 - 533 (2018/01/27)
Abstract: A green, efficient, and rapid procedure for the hydrogenation of nitroarenes to formanilides in Pd(TFA)2/HCOOH system in water is described. Under optimized conditions, the reaction of most substrates is complete within 30?min with yields of 30–93%. Furthermore, this procedure is applied successfully for the modification of natural products, such as arctigenin, vindoline, and estrone. Graphical abstract: [Figure not available: see fulltext.].
New catalytic performance of immobilized sulfuric acid on activated charcoal for n-formylation of amines with ethyl formate
Abdollahi, Mohammad,Zeynizadeh, Behzad,Sadighnia, Leila
, p. 619 - 627 (2017/11/06)
Summary: Simple and highly efficient procedure for N-formylation of various amines was carried out in the presence of the immobilized sufuric acid on activated charcoal as an efficient promoter system. All reactions were taken place in refluxing ethyl formate (54 °C) under mild reaction conditions. The product formamides were obtained in high to excellent yields (83-95%) within 4-80 min.
An efficient method for the synthesis of formamidine and formamide derivatives promoted by sulfonated rice husk ash (RHA-SO3H)
Seddighi, Mohadeseh,Shirini, Farhad,Mamaghani, Manouchehr
, p. 433 - 439 (2015/02/05)
A mild, simple and efficient method has been developed for the promotion of the preparation of N,N′-diphenylformamidines from various aromatic amines and ethyl orthoformate using sulfonated rice husk ash (RHA-SO3H) solid acid catalyst. This reagent has also been used for the N-formylation of a variety of amines using formic acid under solvent-free conditions. The procedures gave the products in very short reaction times and good-to-high yields. Also this catalyst can be reused for five times without loss of its catalytic activity.
The ortho effect on the acidic and alkaline hydrolysis of substituted formanilides
Desai, Salil Dileep,Kirsch, Lee E.
, p. 471 - 488 (2015/06/30)
The kinetics of formanilides hydrolysis were determined under first-order conditions in hydrochloric acid (0.01-8 M, 20-60°C) and in hydroxide solutions (0.01-3 M, 25 and 40°C). Under acidic conditions, second-order specific acid catalytic constants were used to construct Hammett plots. The ortho effect was analyzed using the Fujita-Nishioka method. In alkaline solutions, hydrolysis displayed both first- and second-order dependence in the hydroxide concentration. The specific base catalytic constants were used to construct Hammett plots. Ortho effects were evaluated for the first-order dependence on the hydroxide concentration. Formanilide hydrolyzes in acidic solutions by specific acid catalysis, and the kinetic study results were consistent with the AAC2 mechanism. Ortho substitution led to a decrease in the rates of reaction due to steric inhibition of resonance, retardation due to steric bulk, and through space interactions. The primary hydrolytic pathway in alkaline solutions was consistent with a modified BAC2 mechanism. The Hammett plots for hydrolysis of meta- and para-substituted formanilides in 0.10 M sodium hydroxide solutions did not show substituent effects; however, ortho substitution led to a decrease in rate constants proportional to the steric bulk of the substituent.
