147-82-0Relevant articles and documents
Facile and sensitive spectrophotometric determination of propoxur in formulations and environmental samples
Kumar, Kailasa Suresh,Suvardhan, Kanchi,Rekha, Dasari,Jayaraj,Chiranjeevi, Pattium
, p. 1022 - 1027 (2005)
A facile, rapid, and sensitive spectrophotometric method for the determination of propoxur in insecticidal formulations, fortified water, vegetables, agricultural wastewater, and agricultural soil samples has been elaborated. The proposed method is based on the hydrolysis of propoxur under basic conditions, followed by instantaneous azo coupling of the resulting 2-isopropoxyphenol with the anilines 2a - c. This yielded the orange-red chromophore 3a (λmax = at 470 nm). the pale-red coupling product 3b (490 nm), or the red derivative 3c (478 nm), which are stable for 46 h, 38 h, and 24 h, respectively, and could be readily analyzed spectrophotometrically.
Oxidative bromination of aniline and its derivatives
Salakhov,Bagmanov,Umaeva,Bagmanova
, p. 1479 - 1481 (2008)
Oxidative bromination of aniline and its derivatives containing various substituents (CH3, Cl, NO2, COOH) in ortho, meta, and para positions with a brominating mixture of NaBr (KBr) and 20-22% hydrogen peroxide in 6-8% hydrochloric acid at the molar ratio aniline: NaBr (KBr): H 2O2: HCl = 1: 3.5: 3.2: 4.5 is described.
An alternative synthesis of 2,6-dimethoxyl-1,4-benzoquinone
Wang, Qian,Yang, Jian,Zheng, Yang,Liao, Xiali
, p. 193 - 194 (2017)
An economic four-step synthesis of 2,6-dimethoxy-1,4-benzoquinone was achieved in 68 % overall yield starting from aniline. The reaction sequence involved conversion to1,3,5-tribromoaniline, deamination, methoxylation, and oxidation. The procedure is operationally simple and amenable to scale-up production.
Synthesis method of high-purity phloroglucinol compound
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Paragraph 0018, (2021/06/09)
The invention discloses a one-step chemical catalytic synthesis method of high-purity phloroglucinol by taking 3,5-dichlorophenol as a starting material and taking strong base and a catalyst as auxiliary materials. Through the method, the phloroglucinol compound with high molar yield, high purity and low cost can be effectively synthesized.
A Practical Procedure for Regioselective Bromination of Anilines
Takahashi, Yusuke,Seki, Masahiko
, p. 1828 - 1832 (2021/04/15)
A highly practical procedure for the preparation of bromoanilines by using copper-catalyzed oxidative bromination has been developed. Treatment of free anilines with readily available NaBr and Na 2S 2O 8in the presence of a catalytic amount of CuSO 4·5H 2O enabled regioselective bromination.
Crystal structure, NMR and catalytic properties of a bis-peroxovanadium [NH4][VO(O2)2(mpa)]·H2O
Chen, Ping,Zhang, Shaowei,Zhang, Jie,Xia, Wen,Yu, Xianyong
, p. 239 - 250 (2019/02/01)
By reacting NH4VO3 and mpa (mpa = 4-methoxypicolinamide) in the presence of H2O2, a bis-peroxovanadium [NH4][VO(O2)2(mpa)]·H2O (1) was obtained and characterized by X-ray single-crystal diffraction. Structural analyses demonstrate that 1 belongs to the monoclinic space group P21/c and consists of a bis-peroxovanadium [VO(O2)2(mpa)]?, one NH4+ counterion and one free lattice water. Adjacent [VO(O2)2(mpa)]? anions construct a 3D supramolecular framework through intra- and intermolecular hydrogen bonding interactions. The compositions of 1 in solution are investigated by using multinuclear (1H, 13C, and 51V) magnetic resonance, COSY, HSQC, HMBC, and variable temperature NMR in a 0.15 mol L?1 NaCl/D2O solution that mimics the physiological conditions. Comparing the results of single-crystal X-ray and NMR experiments, the VV ion in the undissociated [VO(O2)2(mpa)]? in solution displays a similar seven-coordinate distorted pentagonal bipyramidal geometry with the solid-state crystal. The catalytic activity of the 1 in the oxidative bromination for phenol/aniline-like compounds to mimic bromoperoxidases reactivity was also studied.
Sodium sulfate-hydrogen peroxide-sodium chloride adduct: selective protocol for the oxidative bromination, iodination and temperature dependent oxidation of sulfides to sulfoxides and sulfones
Gayakwad, Eknath M.,Patel, Khushbu P.,Shankarling, Ganapati S.
supporting information, p. 6001 - 6009 (2019/04/17)
The regioselective bromination and iodination of unprotected aromatic primary amines using enclathrated hydrogen peroxide as an oxidant under mild conditions has been developed, in which potassium bromide (KBr) and potassium iodide (KI) were used as brominating and iodinating agents, respectively. The adduct shows not only regioselectivity for para- or ortho-isomers but also a remarkable chemoselectivity for monobromination. Selective oxidation of sulfides to sulfoxides and sulfones has also been studied and good to excellent yields of the desired products were obtained. Acetic acid was found to be the solvent of choice for these reactions. This simple method represents an ecologically benign and alternative pathway for the oxidative halogenation of anilines and the oxidation of sulfides to sulfoxides and sulfones.
Method of catalytically synthesizing polybromo-aniline in water phase
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Paragraph 0012-0017, (2019/10/04)
The invention discloses a method of catalytically synthesizing polybromo-aniline in a water phase. The method comprises following steps: adding a catalytic amount of a free radical initiator, aniline derivatives, cheap and low-toxic bromine salts, and water into a reactor; carrying out reactions in a photocatalytic reaction instrument under power of 5W at a room temperature; after a while, extracting the reaction product by ethyl acetate, and carrying out recrystallization to obtain polybromo-aniline; wherein the free radical initiator is eosin, sodium persulfate, or potassium persulfate. The power of the incandescent lamp of the photocatalytic reaction instrument is 5W. The free radical initiator and bromine salts are cheap and easily available. The method is an ideal synthesis method of polybromo-aniline. Cheap and low-toxic bromine salts are used to replace liquid bromine. The cheap and easily available free radical initiator is used to replace unstable and explosive hydrogen peroxide. After 4 to 10 hours of reactions under the power of 5W, polybromo-aniline can be synthesized, the yield and the reaction selectivity are high, the byproducts are few, and the post treatment is simple.
Crystal structure and catalytic properties of a vanadium complex cis-[VO2(Him-py)(im-py)]2·3H2O
Sun, Meng,Zhang, Shaowei,Zhang, Jie,Xia, Wen,Chen, Jialiang,Yu, Xianyong
, p. 1899 - 1909 (2019/06/04)
The coordination behavior of Him-py (2-(1H-imidazol-2-yl)pyridine) toward vanadium has been explored. The six-coordinate complex, cis-[VO2(Him-py)(im-py)]2·3H2O (1), was synthesized by the coordination reaction of NH4VO3 and Him-py in the aqueous methanol solution, which was characterized by single-crystal X-ray technology. It belongs to the monoclinic space group P21/n with a = 8.0756(6), b = 19.3531(15), c = 11.4433(8), β = 106.905(2), V = 1711.2(2), and Z = 2. The crystal structure shows that the six-coordinate vanadium is bonded to two cis-oxido ligands and two bidentate ligands, Him-py and im-py. Interestingly, when crystals of 1 were immersed in H2O2, a peroxovanadium compound, (H2im-py)[OV(O2)2(Him-py)] (2), was obtained, which crystallizes in the orthorhombic space group Fdd2 with a = 22.600(2), b = 22.7259(13), c = 18.0146(11), V = 9252.4(12), and Z = 16, and consists of a seven-coordinate peroxovanadate(V) ion, one Him-py and one H2im-py ligand. Moreover, we also studied the catalytic activity of 1 in the oxidative bromination of phenol/aniline-like compounds towards mimicking bromoperoxidase reactivity.
Unusual Chemistry in an Uncatalyzed Bromate-Aniline Oscillator: Ring-Contraction Oxidation of Aniline with Pulsative CO2 Production
Valent, Ivan,Pribus, Marek,Novák, Filip,Plánková, Sylvia,Bla?ko, Jaroslav,Kubinec, Róbert,Almássy, Ambroz,Filo, Juraj,Sigmundová, Ivica,Sebechlebská, Táňa,Lawson, Thuy Bich,Noszticzius, Zoltán
, p. 9669 - 9681 (2019/11/14)
The bromate-aniline oscillatory reaction was discovered 4 decades ago, but neither the detailed mechanism nor the key products or intermediates of the reaction were described. We report herein a detailed study of this reaction, which yielded new insights. We found that oscillatory oxidation of aniline by acidic bromate proceeds, to a significant extent, via a novel reaction pathway with the periodic release of carbon dioxide. Several products were isolated, and their structures, not described so far, were justified on the basis of MS and NMR. One of the main products of the reaction associated with the CO2 release route can be assigned to 2,2-dibromo-5-(phenylimino)cyclopent-3-en-1-one. A number of known compounds produced in the studied reaction, including unexpected brominated 1-phenylpyrroles and 1-phenylmaleimides, were identified by comparison with standards. A mechanism is suggested to explain the appearance of the detected compounds, based on coupling of the anilino radical with the produced 1,4-benzoquinone. We assume that the radical adduct reacts with bromine to form a cyclopropanone intermediate that undergoes a Favorskii-type rearrangement. Further oxidation and bromination steps including decarboxylation lead to the found brominated phenyliminocyclopentenones. The detected derivatives of 1-phenylpyrrole could be produced by a one-electron oxidation of a proposed intermediate 2-phenylamino-5-bromocyclopenta-1,3-dien-1-ol followed by β-scission with the abstraction of carbon monoxide. Such a mechanism is known from the combustion chemistry of cyclopentadiene. The proposed mechanism of this reaction provides a framework for understanding the observed oscillatory kinetics.