156-43-4Relevant articles and documents
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Bergstrom,Horning
, p. 334,336, 339 (1946)
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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.
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.
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.).
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).
