Xn:Harmful;
79-39-0Relevant academic research and scientific papers
Homopolymerization of methacrylamide by anionic process under effect of Maghnite-Na+ (Algerian MMT)
Derkaoui, Samira,Belbachir, Mohammed,Haoue, Sara,Zeggai, Fatima Zohra,Rahmouni, Abdelkader,Ayat, Moulkheir
, p. 52 - 60 (2019)
The present study describes a new way for synthesis of methacrylamide (MAM) and it's homologue polymethacrylamide (PMAM) under effect of montmorillonite clay (Algerian MMT). The interlayer cation of montmorillonite clay was exchanged with Na + protons (anionic process). Monomer was successfully synthesized by the condensation of ammonia with methacrylic anhydride in bulk (without solvent) and the polymer with increasing anionic catalyst (Mag-Na+) in Tetrahydrofuran THF. Furthermore, the obtained monomer (MAM) and polymer (PMAM) were characterized and confirmed by Infrared Spectroscopy (FT-IR), 1H nuclear magnetic resonance (NMR) spectroscopy and Thermal properties by thermogravimetric analysis (TGA). The conversion and yield of monomer-polymer increased with the increase of the amount of catalyst “Maghnite-Na+”, the reactivity of the ammonia related to its basicity and the effect of amine substitution with methacrylic anhydride involved electron donor forces of the substitution group.
Comparison between the electric conductivity of polyhydroxamic acids of different origin
Sayed, Wafaa M.,Abed, Yahia M.,Gad, El-Shafie A.M.,Salem, Tousson A.
, p. 245 - 252 (1998)
Polyhydroxamic acid (PHA) was prepared from polyacrylamide (PAA) and from polymethacrylamide (PMAA). It was found that PHA from PAA has the properties of a semiconductor when it reacts with some metals. PHA from PMAA has typical semiconducting properties when reacting with 1 mmol of ferric chloride, whereas its electric conductivity is somewhat lower when it contains 0.5 mmol of ferric chloride.
Study on the degradation mechanism and pathway of benzene dye intermediate 4-methoxy-2-nitroaniline: Via multiple methods in Fenton oxidation process
Guo, Ying,Xue, Qiang,Cui, Kangping,Zhang, Jia,Wang, Hui,Zhang, Huanzhen,Yuan, Fang,Chen, Honghan
, p. 10764 - 10775 (2018/03/26)
Benzene dye intermediate (BDI) 4-methoxy-2-nitroaniline (4M2NA) wastewater has caused significant environmental concern due to its strong toxicity and potential carcinogenic effects. Reports concerning the degradation of 4M2NA by advanced oxidation process are limited. In this study, 4M2NA degradation by Fenton oxidation has been studied to obtain more insights into the reaction mechanism involved in the oxidation of 4M2NA. Results showed that when the 4M2NA (100 mg L-1) was completely decomposed, the TOC removal efficiency was only 30.70-31.54%, suggesting that some by-products highly recalcitrant to the Fenton oxidation were produced. UV-Vis spectra analysis based on Gauss peak fitting, HPLC analysis combined with two-dimensional correlation spectroscopy and GC-MS detection were carried out to clarify the degradation mechanism and pathway of 4M2NA. A total of nineteen reaction intermediates were identified and two possible degradation pathways were illustrated. Theoretical TOC calculated based on the concentration of oxalic acid, acetic acid, formic acid, and 4M2NA in the degradation process was nearly 94.41-97.11% of the measured TOC, indicating that the oxalic acid, acetic acid and formic acid were the main products. Finally, the predominant degradation pathway was proposed. These results could provide significant information to better understand the degradation mechanism of 4M2NA.
Selective hydration of nitriles to amides catalysed by PCP pincer supported nickel(ii) complexes
Borau-Garcia,Gutsulyak,Burford,Piers
, p. 12082 - 12085 (2016/01/15)
The (PCP)Ni-OH complexes 2R (R = iPr, tBu, Cy) are effective catalyst precursors for the selective hydration of nitriles to the corresponding amides under relatively mild conditions (80 °C) and low catalyst loadings (0.05-0.5%). Substrate scope includes aliphatic, vinylic and aromatic nitriles, but substrates with protic groups poison the catalyst abruptly. The catalysts are effective because the electron rich nature of the PCP ligands and their steric bulk renders the hydroxo group labile.
Synthesis and Structural Characterization of Nickel Complexes Possessing P-Stereogenic Pincer Scaffolds and Their Application in Asymmetric Aza-Michael Reactions
Yang, Zehua,Liu, Delong,Liu, Yangang,Sugiya, Masashi,Imamoto, Tsuneo,Zhang, Wanbin
supporting information, p. 1228 - 1237 (2015/04/27)
Novel P-stereogenic pincer-Ni complexes {κP,κC,κP-3,5-Me2-2,6-(MetBuPCH2)2C6H}NiCl (3), {κP,κC,κP-3,5-Me2-2,6-(MetBuPCH2)2C6H}NiOTf (4), [{κP,κN,κP-2,6-(MetBuPCH2)2C5H3N}NiCl]Cl (7), [{κP,κN,κP-2,6-(MetBuPCH2)2C5H3N}NiCl]BF4 (8), and [{κP,κN,κP-2,6-(MetBuPCH2)2C5H3N}Ni(NCMe)](BF4)2 (9) were synthesized in 55-84% yields and characterized by 1H NMR, 13C{1H} NMR, 31P{1H} NMR, 19F{1H} NMR, and/or single-crystal X-ray diffractions. The ORTEP diagrams of complexes 3, 7, 8, and 9 show that the coordination geometries around the Ni center in all these structures are approximately square planar but have different bond lengths and angles. These complexes were shown to be active catalysts for the asymmetric aza-Michael addition of α,β-unsaturated nitriles. For most examples good to excellent yields (up to 99%) and moderate enantiomeric excesses (up to 46% ee) were obtained. Notably, the PCP complex 3 exhibited higher catalytic activity in the aza-Michael addition than the PNP complexes 7, 8, and 9. Two achiral PCP-type pincer-Ni complexes, {κP,κC,κP-3,5-Me2-2,6-(tBu2PCH2)2C6H}NiCl (11) and {κP,κC,κP-3,5-Me2-2,6-(Ph2PCH2)2C6H}NiCl (13), were also synthesized and fully characterized in order to reveal the structural differences between the chiral and achiral complexes. (Chemical Equation Presented).
Metal complex compound and process for producing amides utilizing the metal complex compound
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Page/Page column 27, (2014/05/20)
A catalyst contains a metal complex compound represented by the following general formula (I). In the formula (I), M is a metal ion such as ruthenium, L1 is a cyclic or acyclic, neutral or minus 1-valent unsaturated hydrocarbon group of 1 to 30 carbon atoms which may have a substituent, L2 and L3 are each independently chlorine or the like, and L4 is a compound bonded to M through phosphorus or arsenic and represented by the following general formula (IIa) or (IIb). In the formulas (IIa) and (IIb), E is phosphorus or arsenic, Y1 is oxygen or sulfur, Y2, Y3 and Y4 are each independently a hydrogen atom, an aryl group or the like, and H is a hydrogen atom.
Catalytic nitrile hydration with [Ru(η6- p -cymene)Cl 2(PR2R′)] complexes: Secondary coordination sphere effects with phosphine oxide and phosphinite ligands
Knapp, Spring Melody M.,Sherbow, Tobias J.,Yelle, Robert B.,Juliette, J. Jerrick,Tyler, David R.
supporting information, p. 3744 - 3752 (2013/07/26)
The rates of nitrile hydration reactions were investigated using [Ru(η6-p-cymene)Cl2(PR2R′)] complexes as homogeneous catalysts, where PR2R′ = PMe 2(CH2P(O)Me2), PMe2(CH 2CH2P(O)Me2), PPh2(CH 2P(O)Ph2), PPh2(CH2CH 2P(O)Ph2), PMe2OH, P(OEt)2OH. These catalysts were studied because the rate of the nitrile-to-amide hydration reaction was hypothesized to be affected by the position of the hydrogen bond accepting group in the secondary coordination sphere of the catalyst. Experiments showed that the rate of nitrile hydration was fastest when using [Ru(η6-p-cymene)Cl2PMe2OH]: i.e., the catalyst with the hydrogen bond accepting group capable of forming the most stable ring in the transition state of the rate-limiting step. This catalyst is also active at pH 3.5 and at low temperatures - conditions where α-hydroxynitriles (cyanohydrins) produce less cyanide, a known poison for organometallic nitrile hydration catalysts. The [Ru(η6-p-cymene) Cl2PMe2OH] catalyst completely converts the cyanohydrins glycolonitrile and lactonitrile to their corresponding α-hydroxyamides faster than previously investigated catalysts. [Ru(η6-p-cymene) Cl2PMe2OH] is not, however, a good catalyst for acetone cyanohydrin hydration, because it is susceptible to cyanide poisoning. Protecting the -OH group of acetone cyanohydrin was shown to be an effective way to prevent cyanide poisoning, resulting in quantitative hydration of acetone cyanohydrin acetate.
Cyclization of the semicarbazones to 1,3,4-oxadiazole derivatives using ceric ammonium nitrate as oxidant
Vahedi,Lari,Bavand,Ameri
experimental part, p. 288 - 290 (2012/08/08)
Cyclization of the semicarbazones to 1,3,4-oxadiazole using ceric ammonium nitrate as oxidant was studied. 2-Imino-1,3,4-oxadiazolines can be produced from semicarbazones, which undergo thermolysis to amides. Benzoic acid benzylidene hydrazide can also be cyclized to 2-methoxy-2-phenyl-1,3,4-oxadiazole in the presence of ceric ammonium nitrate and methanol.
A general and efficient heterogeneous gold-catalyzed hydration of nitriles in neat water under mild atmospheric conditions
Liu, Yong-Mei,He, Lin,Wang, Miao-Miao,Cao, Yong,He, He-Yong,Fan, Kang-Nian
scheme or table, p. 1392 - 1396 (2012/10/07)
Mild, efficient and general: Titania decorated with nanometer-sized gold particles acts as an efficient catalyst for the selective hydration of a wide range of chemically diverse nitriles into valuable amides in neutral water, under mild atmospheric conditions (see image). The process shows promise for a facile and direct one-pot synthesis of ?μ-caprolactam, an industrially important molecule, starting from 6-aminocapronitrile. Copyright
Natural kaolin supported sulfuric acid as an efficient catalyst for selective hydrolysis of nitriles to amides
Gordi, Zinat,Eshghi, Hossein
experimental part, p. 715 - 718 (2011/10/08)
The natural kaolin supported sulfuric acid as an efficient catalyst for selective hydrolysis of nitriles to amides was investigated. The nitrile (4 mmol) was dissolved in water (10 mL) in the presence of kaolin and refluxed for 24 h. The crude product was extracted with ethyl acetate in 55-80% yields after completion of the reaction (monitored by TLC). Careful neutralization of all reaction mixtures were carried out to pH = 7 for exact monitoring of reaction for possible formation of carboxylic acid. The products were characterized by IR and 1H NMR spectroscopy and also their melting points are compared with authentic samples. The disappearance of one strong and sharp absorption band (CN stretching band), and the appearance of two NH2 stretching bands in 3370 and 3320 cm-1 and carboxamide stretching in 1650 cm-1 in the IR spectra, were evidence for the formation of primary amides.
