79128-85-1Relevant academic research and scientific papers
Switching Selectivity in Copper-Catalyzed Transfer Hydrogenation of Nitriles to Primary Amine-Boranes and Secondary Amines under Mild Conditions
Song, Hao,Xiao, Yao,Zhang, Zhuohua,Xiong, Wanjin,Wang, Ren,Guo, Liangcheng,Zhou, Taigang
, p. 790 - 800 (2022/01/11)
A simple and efficient copper-catalyzed selective transfer hydrogenation of nitriles to primary amine-boranes and secondary amines with an oxazaborolidine-BH3 complex is reported. The selectivity control was achieved under mild conditions by switching the solvent and the copper catalysts. More than 30 primary amine-boranes and 40 secondary amines were synthesized via this strategy in high selectivity and yields of up to 95%. The strategy was applied to the synthesis of 15N labeled in 89% yield.
Nickel Complexes Bearing N,N,O-Tridentate Salicylaldiminato Ligand: Efficient Catalysts for Imines Formation via Dehydrogenative Coupling of Primary Alcohols with Amines
Han, Zhangang,Hao, Zhiqiang,Lin, Jin,Lu, Guo-Liang,Zhang, Junhua,Zhang, Xiaoying
, p. 3843 - 3853 (2021/11/18)
Treatment of salicylaldiminato ligand L1H-L2H (L1H = 2,4-di-tert-butyl-6-((quinolin-8-ylimino)methyl)phenol; L2H = 2,4-di-tert-butyl-6-(((2-(diethylamino)ethyl)imino)methyl)phenol) with Ni(OAc)2·4H2O in refluxing ethanol afforded nickel complexes [(L1)Ni(OAc)] (1) and [(L2)Ni(OAc)] (2), respectively. Reaction of L3H (L3H = (2,4-di-tert-butyl-6-(((2-(pyridin-2-yl)ethyl)imino)methyl)phenol)) with Ni(OAc)2·4H2O in the presence of excess triethylanmine gave the dual ligands coordinated nickel complex [(L2)2Ni] (3). Complexes 1-3 were well characterized by high-resolution mass spectrometry, infrared spectroscopy, elemental analysis, and X-ray diffraction analysis. All the three Ni(II) complexes exhibited efficient activity and good selectivity in the acceptorless dehydrogenative coupling of alcohols and amines to produce imines and diimines. The present protocol provides an atom-economical and sustainable route for the synthesis of various imine derivatives by employing an earth-abundant nickel salt and easily prepared salicylaldiminato ligands.
Homogeneous cobalt-catalyzed deoxygenative hydrogenation of amides to amines
Papa, Veronica,Cabrero-Antonino, Jose R.,Spannenberg, Anke,Junge, Kathrin,Beller, Matthias
, p. 6116 - 6128 (2020/11/03)
The first general and efficient cobalt-catalyzed deoxygenative hydrogenation of amides to amines is presented. The optimal catalytic system based on a combination of [Co(NTf2)2] and (p-anisyl)triphos (L3) in the presence of [Me3SiOTf] as acidic co-catalyst facilitates the direct hydrogenation of a broad range of amides to the corresponding amines under mild conditions. A set of control experiments indicate that, after the initial reduction of the amide carboxylic group to the well-known hemiaminal intermediate, the reaction mainly proceeds through C-O bond cleavage though other pathways might be also involved to a minor extent. This journal is
Homoleptic Bis(trimethylsilyl)amides of Yttrium Complexes Catalyzed Hydroboration Reduction of Amides to Amines
Ye, Pengqing,Shao, Yinlin,Ye, Xuanzeng,Zhang, Fangjun,Li, Renhao,Sun, Jiani,Xu, Beihang,Chen, Jiuxi
, p. 1306 - 1310 (2020/02/22)
Homoleptic lanthanide complex Y[N(TMS)2]3 is an efficient homogeneous catalyst for the hydroboration reduction of secondary amides and tertiary amides to corresponding amines. A series of amides containing different functional groups such as cyano, nitro, and vinyl groups were found to be well-tolerated. This transformation has also been nicely applied to the synthesis of indoles and piribedil. Detailed isotopic labeling experiments, control experiments, and kinetic studies provided cumulative evidence to elucidate the reaction mechanism.
Secondary amine derivative synthesized through rare earth catalysis, and preparation method thereof
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Paragraph 0057; 0058; 0059; 0060; 0061; 0062, (2020/03/12)
The invention discloses a secondary amine derivative synthesized through rare earth catalysis, and a preparation method thereof. According to the preparation method, the secondary amine derivative isprepared by carrying out a reaction on reactants of secondary amide and pinacol borane; a rare earth catalyst bis(trimethylsilyl) amino yttrium is added; the reaction temperature is 100-140 DEG C, andthe reaction time is 20-25 h; the whole reaction is carried out under a normal pressure, and the reaction conditions are mild, easy to achieve and safe; the method is simple and convenient to operateand high in reaction selectivity, can directly synthesize the target product without intermediate product separation, can obtain the target product only through a reaction under a normal pressure, issimple in reaction process, has the yield of 90% at most, substantially simplifies the process engineering, reduces the energy consumption, and has high yield; the reaction raw materials are stable and easy to store; a series of secondary amine derivatives can be prepared; and the method has high substrate universality so as to provide the good guarantee for development of related substances related to secondary amine derivatives, and is suitable for large-scale application and popularization.
A practical catalytic reductive amination of carboxylic acids
Andrews, Keith G.,Denton, Ross M.,Hirst, David J.,Stoll, Emma L.,Tongue, Thomas,Valette, Damien
, p. 9494 - 9500 (2020/10/02)
We report reductive alkylation reactions of amines using carboxylic acids as nominal electrophiles. The two-step reaction exploits the dual reactivity of phenylsilane and involves a silane-mediated amidation followed by a Zn(OAc)2-catalyzed amide reduction. The reaction is applicable to a wide range of amines and carboxylic acids and has been demonstrated on a large scale (305 mmol of amine). The rate differential between the reduction of tertiary and secondary amide intermediates is exemplified in a convergent synthesis of the antiretroviral medicine maraviroc. Mechanistic studies demonstrate that a residual 0.5 equivalents of carboxylic acid from the amidation step is responsible for the generation of silane reductants with augmented reactivity, which allow secondary amides, previously unreactive in zinc/phenylsilane systems, to be reduced.
Mesoporous cobalt/manganese oxide: A highly selective bifunctional catalyst for amine-imine transformations
Dutta, Biswanath,March, Seth,Achola, Laura,Sahoo, Sanjubala,He, Junkai,Shirazi Amin, Alireza,Wu, Yang,Poges, Shannon,Pamir Alpay,Suib, Steven L.
supporting information, p. 3180 - 3185 (2018/07/29)
Herein, we discuss a heterogeneous catalytic protocol using cobalt doped mesoporous manganese oxide for amine-alcohol cross-coupling to selectively produce symmetric or asymmetric imines. Thorough investigations on the surface chemistry and physical properties of the material revealed its outstanding oxidation-reduction properties and reaction mechanism which was supported by quantum mechanical calculations done by using density functional theory (DFT).
Nickel-Catalyzed Reduction of Secondary and Tertiary Amides
Simmons, Bryan J.,Hoffmann, Marie,Hwang, Jaeyeon,Jackl, Moritz K.,Garg, Neil K.
supporting information, p. 1910 - 1913 (2017/04/11)
The nickel-catalyzed reduction of secondary and tertiary amides to give amine products is reported. The transformation is tolerant of extensive variation with respect to the amide substrate, proceeds in the presence of esters and epimerizable stereocenters, and can be used to achieve the reduction of lactams. Moreover, this methodology provides a simple tactic for accessing medicinally relevant α-deuterated amines.
Nucleophilic substitution reactions of meta- and para-substituted benzylamines with benzyl bromide in methanol medium
Ravi,Sanjeev,Jagannadham,Skelton, Adam A.
, p. 36 - 41 (2015/02/19)
The rates of reactions of para- and meta-substituted benzylamines with benzyl bromide were measured using conductivity technique in methanol medium. The reaction followed a total second-order path. The end product of the reaction is identified as dibenzylamine (X-C6H4CH2NHCH2C6H5) (where X = 4-OCH3, 4-CH3, H, 4-Cl, 4-CF3, 3-CF3, 4-NO2). Electron-withdrawing groups such as chloro, trifluoromethyl, and nitro in the benzylamine moiety decrease the rate of the reaction, whereas the electron-donating groups, such as methoxy and methyl, increase the rate compared to the unsubstituted compound. A mechanism involving formation of an SN 2-type transition state between the amine nucleophiles and the benzyl bromide and its subsequent decomposition is proposed. Hammett's reaction constant ρ of the reaction decreases with an increase in temperature. Activation parameters were calculated and discussed.
