94718-79-3Relevant academic research and scientific papers
Selective and Additive-Free Hydrogenation of Nitroarenes Mediated by a DMSO-Tagged Molecular Cobalt Corrole Catalyst
Sch?fberger, Wolfgang,Timelthaler, Daniel,Topf, Christoph
supporting information, p. 2114 - 2120 (2021/07/22)
We report on the first cobalt corrole that effectively mediates the homogeneous hydrogenation of structurally diverse nitroarenes to afford the corresponding amines. The given catalyst is easily assembled prior to use from 4-tert-butylbenzaldehyde and pyrrole followed by metalation of the resulting corrole macrocycle with cobalt(II) acetate. The thus-prepared complex is self-contained in that the hydrogenation protocol is free from the requirement for adding any auxiliary reagent to elicit the catalytic activity of the applied metal complex. Moreover, a containment system is not required for the assembly of the hydrogenation reaction set-up as both the autoclave and the reaction vessels are readily charged under a regular laboratory atmosphere.
Synthesis of 7-halo indoles (by machine translation)
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Paragraph 0025, (2017/01/12)
The present invention relates to synthesis of 7? Halo indole method, comprising the steps of:O-halogenated aniline, chloral hydrate and hydroxylamine hydrochloride by the Sandmeyer reaction to synthesize 7? halogenating isatin ; 7? halogenating isatin dissolved with an organic solvent, in the reducing agent by reduction reaction under the conditions of 7? Halo indole, the reducing agent is an alkali metal borohydride system, four system adopts, lithium hydride system or triethyl silane system. The beneficial effect of the invention is:in order to O-halogenated aniline and the chloral hydrate is, hydroxylamine hydrochloride as raw materials, by the Sandmeyer shall synthesis method for preparing compositions b isonitroso 7? halogenating isatin, and then by further reduction and system reduction to prepare 7? Halo indole; by the 7? Preparation halogenating isatin 7? Halo indole method, the raw material is easy to obtain, low price, higher process yield, the product purity is good, simple operation, and the like, is suitable for batch preparation 7? Halo indole. (by machine translation)
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.
Weak halogen bonding in solid haloanilinium halides probed directly via chlorine-35, bromine-81, and iodine-127 NMR spectroscopy
Attrell, Robert J.,Widdifield, Cory M.,Korobkov, Ilia,Bryce, David L.
experimental part, p. 1641 - 1653 (2012/06/30)
A series of monohaloanilinium halides exhibiting weak halogen bonding (XB) has been prepared and characterized by 35Cl, 81Br, and 127I solid-state nuclear magnetic resonance (SSNMR) spectroscopy in magnetic fields of up to 21.1 T. The quadrupolar and chemical shift (CS) tensor parameters for halide ions (Cl-, Br-, I-) which act as electron density donors in the halogen bonds of these compounds are measured to provide insight into the possible relationship between halogen bonding and NMR observables. The NMR data for certain series of related compounds are strongly indicative of when such compounds pack in the same space group, thus providing practical structural information. Careful interpretation of the NMR data in the context of novel and previously available X-ray crystallographic data, and new gauge-including projector-augmented-wave density functional theory (GIPAW DFT) calculations has revealed several notable trends. When a series of related compounds pack in the same space group, it has been possible to interpret trends in the NMR data in terms of the strength of the halogen bond. For example, in isostructural series, the halide quadrupolar coupling constant was found to increase as the halogen bond weakens. In the case of a series of haloanilinium bromides, the 81Br isotropic chemical shift and CS tensor span both decrease as the bromide-halogen XB is weakened. These trends were reproduced using both GIPAW DFT and cluster-model calculations of the bromide ion magnetic shielding tensor. Such trends are particularly exciting given the well-known role that NMR has played historically in the characterization of hydrogen bonding.
Alternative method for the reduction of aromatic nitro to amine using TMDS-iron catalyst system
Pehlivan, Leyla,Métay, Estelle,Laval, Stéphane,Dayoub, Wissam,Demonchaux, Patrice,Mignani, Gérard,Lemaire, Marc
experimental part, p. 1971 - 1976 (2011/04/22)
The system 1,1,3,3-tetramethyldisiloxane (TMDS)/Fe(acac)3 is reported here as a new method to obtain amines from aromatic nitro compounds. Amines are synthetized in a straightforward step and are isolated as hydrochloride salts with good to excellent yields. This system has shown a good selectivity toward aryl-chloride, aryl-bromide, ester, carboxylic acid, and cyano groups. The reduction of alkylnitro compounds was unfortunately not possible using this method, only a mixture of mono and dialkylated amine was obtained.
Iron-catalyzed selective reduction of nitro compounds to amines
Pehlivan, Leyla,Métay, Estelle,Laval, Stéphane,Dayoub, Wissam,Demonchaux, Patrice,Mignani, Gérard,Lemaire, Marc
experimental part, p. 1939 - 1941 (2010/06/14)
An efficient reduction of the nitro group with a catalytic amount of Fe(acac)3 and TMDS in THF at 60 °C affording the corresponding amine is described.
