156-43-4Relevant articles and documents
Mechanism of metabolic activation of the analgetic bucetin to bacterial mutagens by hamster liver microsomes
Nohmi,Ishidate Jr.,Hiratsuka,Watabe
, p. 2877 - 2885 (1985)
Bucetin (N-(β-hydroxybutyryl)-p-phenetidine) was found to be mutagenic to Salmonella typhimurium TA100 in the presence of liver 9000 g supernatant fractions (S9) prepared from polychlorinated biphenyl (PCB)-treated hamsters and a reduced nicotinamide adenine dinucleotidephosphate (NADPH)-generating system. However, the analgetic was not mutagenic in the presence of NADPH-fortified S9 from PCB-treated rat liver. The mutagenic potency of bucetin was about a quarter of that of the structurally related analgetic, phenacetin. PCB-treated hamster liver microsomes fortified with NADPH activated bucetin to two direct-acting mutagens, N-hydroxy-phenetidine and p-nitrosophenetole, through deacylation followed by N-hydroxylation. The nitroso compound arose from N-hydroxyphenetidine via autoxidation. N-(b-Hydroxybutyryl)-p-amino-phenol, a major metabolite of bucetin under the conditions used, was not mutagenic to TA100 either with or without NADPH-fortified S9 from PCB-treated or untreated rats or hamsters. N-Hydroxybucetin, which was about 70 times less mutagenic than N-hydroxyphenacetin in the presence of PCB-treated hamster S9, was not detected as a metabolite of bucetin from the NADPH-fortified reaction mixtures. Although no species difference was observed in p-phenetidine N-hydroxylation, the rate of bucetin deacylation was over 90 times higher in hamsters than in rats. The rate of microsomal deacylation of bucetin was much lower than that of phenacetin or N-butyryl-p-phenetidine. These results suggest that the species difference in bucetin mutagenicity is due to the difference in deacylating activity between rat and hamster liver microsomes, and also that the β-hydroxyl group in the butyryl side chain makes bucetin poorly hydrolyzable in microsomes, resulting in lower mutagenic activity as compared with phenacetin.
Effect of Meta and Para Substituents on the Stannous Chloride Reduction of Nitrobenzenes in Aqueous Ethanol
Xing, Wen-Kang,Ogata, Yoshiro
, p. 2515 - 2520 (1983)
The rate of reduction of 24 meta- and para-substituted nitrobenzenes with SnCl2 catalyzed by HCl in ethanol-water (90 : 10 v/v) at 30 degC has been measured iodometrically.The rate is expressed as υ = kst0.5, suggesting that the sole active reducing species is SnCl3- and the dissociation of HCl is very small.The effect of meta and para substituents in which the solvation of the substituent is taken into account was examined with the Hammett equation, which gave a ρ value of 2.1 +/- 0.1.Yukawa-Tsuno and Taft equations, in which resonance and inductive effects are separated, are also discussed.
Colloid and nanosized catalysts in organic synthesis: V. Reactions of alkyl halides and alcohols with ?2-diketones in the presence of metal nanoparticles
Popov,Mokhov
, p. 1491 - 1495 (2014)
Reaction of copper, nickel, and iron nanoparticles with ?2-diketones directly yields corresponding metal ?2-diketonates. Reaction of alkyl halides, ?2-diketones, and nanodispersed metals leads to a mixture of monoketone and the alkylated ?2-diketone. When alcohol is used as the alkylating agent instead of alkyl halide, corresponding ester is formed.
Cyclic (Alkyl)(amino)carbene Ligand-Promoted Nitro Deoxygenative Hydroboration with Chromium Catalysis: Scope, Mechanism, and Applications
Zhao, Lixing,Hu, Chenyang,Cong, Xuefeng,Deng, Gongda,Liu, Liu Leo,Luo, Meiming,Zeng, Xiaoming
supporting information, p. 1618 - 1629 (2021/01/25)
Transition metal catalysis that utilizes N-heterocyclic carbenes as noninnocent ligands in promoting transformations has not been well studied. We report here a cyclic (alkyl)(amino)carbene (CAAC) ligand-promoted nitro deoxygenative hydroboration with cost-effective chromium catalysis. Using 1 mol % of CAAC-Cr precatalyst, the addition of HBpin to nitro scaffolds leads to deoxygenation, allowing for the retention of various reducible functionalities and the compatibility of sensitive groups toward hydroboration, thereby providing a mild, chemoselective, and facile strategy to form anilines, as well as heteroaryl and aliphatic amine derivatives, with broad scope and particularly high turnover numbers (up to 1.8 × 106). Mechanistic studies, based on theoretical calculations, indicate that the CAAC ligand plays an important role in promoting polarity reversal of hydride of HBpin; it serves as an H-shuttle to facilitate deoxygenative hydroboration. The preparation of several commercially available pharmaceuticals by means of this strategy highlights its potential application in medicinal chemistry.
Selective reduction of nitro-compounds to primary amines by tetrapyridinoporphyrazinato zinc (II) supported on DFNS
Hosseiny, Malihesadat,Khosroyar, Susan,Kiani, Zahra,Motavalizadehkakhky, Alireza,Zhiani, Rahele
, (2021/06/14)
Here, we created and synthesized a heterogeneous catalyst from porphyrazinatozinc (tmtppa-Zn) supported on DFNS (tmtppa-Zn/DFNS). This is a simple method for hydrogenation of nitro-compounds and their conversion to primary amines without producing toxic by-products. These reactions take place under mild reaction situations. The catalyst system was comfortably retrieved and reutilized in at least ten runs without the reduction of catalytic activity.
Mechanochemical Transformation of CF3 Group: Synthesis of Amides and Schiff Bases
Mkrtchyan, Satenik,Jakubczyk, Micha?,Lanka, Suneel,Yar, Muhammad,Ayub, Khurshid,Shkoor, Mohanad,Pittelkow, Michael,Iaroshenko, Viktor O.
supporting information, p. 5448 - 5460 (2021/10/19)
We communicate two mild, solvent-free mechanochemical coupling transformations of CF3 group with nitro compounds into amides or Schiff bases employing Ytterbia as a catalyst. This process proceeds via C?F bond activation, accompanied with utilisation of Si-based reductants/oxygen scavengers – reductants of the nitro group. The scope and limitations of the disclosed methodologies are thoroughly studied. To the best of our knowledge, this work is the first example of mechanical energy promoted transformation of the inert CF3 group into other functionalities. (Figure presented.).
Green synthesis method of p-aminophenetole
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Paragraph 0005; 0008-0010, (2020/02/10)
The invention relates to a green synthesis method of p-aminophenetole, and belongs to the field of preparation methods of chemical products. The synthesis method mainly comprises the following steps:adding raw material p-nitrophenetole into a reduction reaction kettle, performing a hydrogenation reduction reaction under the conditions of no solvent and Raney nickel as a catalyst, after the reaction is finished, cooling, filtering at normal pressure to recover the catalyst, and performing negative-pressure rectification on filtrate to obtain p-aminophenetole. The solvent-free technological conditions are adopted in the whole process, and emission of organic matters in a traditional production process is reduced; the problem that solvents such as methanol are subjected to reaction with reduced amino to generate carbaryl by-products is solved, and the product purity is improved; compared with a conventional solvent method, the green synthesis method has the advantages of lower temperature and lower energy consumption, reduces the production cost, and facilitates energy conservation and emission reduction.
Superior activity and selectivity of heterogenized cobalt catalysts for hydrogenation of nitroarenes
Li, Wu,Artz, Jens,Broicher, Cornelia,Junge, Kathrin,Hartmann, Heinrich,Besmehn, Astrid,Palkovits, Regina,Beller, Matthias
, p. 157 - 162 (2019/01/10)
The development of improved catalysts for highly selective hydrogenation of nitroarenes is described. For this purpose Co nanoparticles were supported on ordered mesoporous carbon CMK-3 and characterized in detail. The optimal CMK-3-CoPc catalyst exhibits excellent hydrogenation activity for several (hetero)aromatic nitro compounds and yielded the corresponding anilines under mild conditions (40 °C, 20 bar H2).
Reversible Formation of a Light-Responsive Catalyst by Utilizing Intermolecular Cooperative Effects
Ren, Chloe Z.-J.,Solís Mu?ana, Pablo,Dupont, Julien,Zhou, Silvia Siru,Chen, Jack L.-Y.
supporting information, p. 15254 - 15258 (2019/10/22)
A photoresponsive system where structure formation is coupled to catalytic activity is presented. The observed catalytic activity is reliant on intermolecular cooperative effects that are present when amphiphiles assemble into vesicular structures. Photoresponsive units within the amphiphilic pre-catalysts allow for switching between assembled and disassembled states, thereby modulating the catalytic activity. The ability to reversibly form cooperative catalysts within a dynamic self-assembled system represents a conceptually new tool for the design of complex artificial systems in water.
Novel Biomass-Derived Fe3O4@Pd NPs as Efficient and Sustainable Nanocatalyst for Nitroarene Reduction in Aqueous Media
Zhao, Linwei,Zheng, Kai,Tong, Jianying,Jin, Jianzhong,Shen, Chao
, p. 2607 - 2613 (2019/06/08)
Abstract: A novel magnetically recyclable nitrogen-doped Fe3O4@Pd NPs was prepared from the biomass-based materials which was employed as carbon and nitrogen source. The as-prepared catalysts were fully characterized by a variety of physicochemical techniques and were exploited for nitroaromatic hydrogenation with broad scope and excellent chemoselectivity using molecular hydrogen as a reductant. The heterogeneous catalysts can be recovered easily and reused for at least eight recycling reactions without obviously loss of catalytic properties. In addition, using this protocol, the key intermediate of marketed drug Osimertinib could be synthesized easily. Graphical Abstract: [Figure not available: see fulltext.].
