24619-87-2Relevant academic research and scientific papers
Simplified preparation of a graphene-co-shelled Ni/NiO@C nano-catalyst and its application in theN-dimethylation synthesis of amines under mild conditions
Liu, Jianguo,Ma, Longlong,Song, Yanpei,Zhang, Mingyue,Zhuang, Xiuzheng
supporting information, p. 4604 - 4617 (2021/06/30)
The development of Earth-abundant, reusable and non-toxic heterogeneous catalysts to be applied in the pharmaceutical industry for bio-active relevant compound synthesis remains an important goal of general chemical research.N-methylated compounds, as one of the most essential bioactive compounds, have been widely used in the fine and bulk chemical industries for the production of high-value chemicals. Herein, an environmentally friendly and simplified method for the preparation of graphene encapsulated Ni/NiO nanoalloy catalysts (Ni/NiO@C) was developed for the first time, for the highly selective synthesis ofN-methylated compounds using various functional amines and aldehydes under easy to handle, and industrially applicable conditions. A large number of primary and secondary amines (more than 70 examples) could be converted to the correspondingN,N-dimethylamines with the participation of different functional aldehydes, with an average yield of over 95%. A gram-scale synthesis also demonstrated a similar yield when compared with the benchmark test. In addition, it was further proved that the catalyst could easily be recycled because of its intrinsic magnetism and reused up to 10 times without losing its activity and selectivity. Also, for the first time, the tandem synthesis ofN,N-dimethylamine products in a one-pot process, using only a single earth-abundant metal catalyst, whose activity and selectivity were more than 99% and 94%, respectively, for all tested substrates, was developed. Overall, the advantages of this newly developed method include operational simplicity, high stability, easy recyclability, cost-effectiveness of the catalyst, and good functional group compatibility for the synthesis ofN-methylation products as well as the industrially applicable tandem synthesis process.
Consecutive β,β′-Selective C(sp3)?H Silylation of Tertiary Amines with Dihydrosilanes Catalyzed by B(C6F5)3
Fang, Huaquan,Xie, Kaixue,Kemper, Sebastian,Oestreich, Martin
supporting information, p. 8542 - 8546 (2021/03/08)
Tris(pentafluorophenyl)borane has been found to catalyze the two-fold C(sp3)?H silylation of various trialkylamine derivatives with dihydrosilanes, furnishing the corresponding 4-silapiperidines in decent yields. The multi-step reaction cascade involves amine-to-enamine dehydrogenation at two alkyl residues and two electrophilic silylation reactions of those enamines, one inter- and one intramolecular.
Simple Metal-Free Direct Reductive Amination Using Hydrosilatrane to Form Secondary and Tertiary Amines
Varjosaari, Sami E.,Skrypai, Vladislav,Suating, Paolo,Hurley, Joseph J. M.,Lio, Ashley M. De,Gilbert, Thomas M.,Adler, Marc J.
supporting information, p. 1872 - 1878 (2017/06/09)
This work describes the use of cheap, safe, and easy-to-handle hydrosilatrane as the reductant in direct reductive amination reactions. This efficient method enables a facile, metal-free access to secondary and tertiary amines from a wide range of aldehydes and ketones, with the synthesis of tertiary amines requiring no additives at all. This reaction demonstrates excellent functional group tolerance, chemoselectivity, and scalability. (Figure presented.).
Pd-Catalyzed Suzuki coupling reactions of aryl halides containing basic nitrogen centers with arylboronic acids in water in the absence of added base
Li, Zhao,Gelbaum, Carol,Campbell, Zachary S.,Gould, Paul C.,Fisk, Jason S.,Holden, Bruce,Jaganathan, Arvind,Whiteker, Gregory T.,Pollet, Pamela,Liotta, Charles L.
, p. 15420 - 15432 (2017/12/15)
The Pd-catalyzed Suzuki coupling reactions of a series of aryl chlorides and aryl bromides containing basic nitrogen centers with arylboronic acids in water in the absence of added base are reported. The reactions proceed either partially or entirely under acidic conditions. After surveying twenty-two phosphorus ligands, high yields of products were obtained with aryl chlorides only when a bulky ligand, 2-(di-tert-butyl-phosphino)-1-phenyl-1H-pyrrole (cataCXiumPtB) was used. In contrast, aryl bromides produced high yields of products in the absence of both added base and added ligand. In order to explore the Suzuki coupling process entirely under acidic conditions, a series of reactions were conducted in buffered acidic media using several model substrates. 4-Chlorobenzylamine, in the presence of cataCXiumPtB, produced high yields of product at buffered pH 6.0; the yields dropped off precipitously at buffered pH 5.0 and lower. The fall-off in yield was attributed to the decomposition of the Pd-ligand complex due to the protonation of the ligand in the more acidic aqueous media. In contrast, in the absence of an added ligand, 4-amino-2-chloropyridine produced quantitative yields at buffered pH 3.5 and 4.5 while 4-amino-2-bromopyridine produced quantitative yields in a series of buffered media ranging from pH 4.5 to 1.5. These substrates are only partially protonated in acidic media and can behave as active Pd ligands in the Suzuki catalytic cycle.
Direct reductive amination and selective 1,2-reduction of α,β-unsaturated aldehydes and ketones by NaBH4 using H3PW12O40 as catalyst
Heydari, Akbar,Khaksar, Samad,Akbari, Jafar,Esfandyari, Maryam,Pourayoubi, Mehrdad,Tajbakhsh, Mahmoud
, p. 1135 - 1138 (2007/10/03)
A simple and convenient procedure for direct reductive amination of aldehydes and ketones with sodium borohydride is described. The reaction has been carried out in methanol in the presence of a catalytic amount of H3PW12O40 (0.5 mol %). α,β-Unsaturated aldehydes and ketones can be easily converted into the corresponding allyl alcohols by reaction with H3PW12O40 (0.5 mol %)/NaBH4.
A general one-pot, three-component mono N-alkylation of amines and amine derivatives in lithium perchlorate/diethyl ether solution
Heydari, Akbar,Tavakol, Hossein,Aslanzadeh, Saied,Azarnia, Jamshid,Ahmadi, Nafiseh
, p. 627 - 633 (2007/10/03)
An efficient, general procedure for reductive monoalkylation of amines and amine derivatives with aldehydes is reported. Treatment of aldehydes with primary amines, secondary amines, O-trimethylsilylhydroxylamine, and N,N-dimethylhydrazine in lithium perc
Titanocene-catalyzed coupling of aromatic amides in the presence of organosilanes: A novel route to vicinal diamines and a new class of amine-substituted oligomers
Rangareddy, Kesamreddy,Selvakumar, Kumaravel,Harrod, John F.
, p. 6843 - 6850 (2007/10/03)
The title reaction has been surveyed for a number of substrates with differing substitution patterns. With a few exceptions, the methodology provides a one-pot synthesis of the 1,2-diamines from widely available and inexpensive starting materials, and in high yields. In addition, the coupling of 1,4-and 1,3-bis-(N,N,N′,N′-tetraalkyl)arylenediamides is shown, under the same experimental conditions, to yield oligomers: R2NC(O)C 6H4CH(NR2)-[CH(NR2)C 6H4CH(NR2)]n-CH(NR 2)C6H4C(O)-NR2 (R = methyl and ethyl; n = 0 to ca. 5). The chemical structures of these unprecedented oligomers are determined by comparison of NMR and MS spectra to those of vicinal diamines, prepared from the analogous N,N-dialkylbenzamides. The origin of the limitation of oligomer chain length is probably due to a specific effect of the internal benzylic amine group, since the substrate 4-Me2NCH 2C6H4C(O)NMe2 was found to be uniquely unreactive compared to the other 4-substituted N,N-dialkylbenzamides investigated. N-Methylphthalimide was briefly studied as a monomer and analysis by MS showed that oligomers are formed. Attempts to fully characterize these polymers were unsuccessful.
Lewis acid-catalyzed reductive amination of carbonyl compounds with aminohydrosilanes
Miura,Ootsuka,Suda,Nishikori,Hosomi
, p. 1617 - 1619 (2007/10/03)
The TiCl4-catalyzed reaction of aromatic carbonyl compounds with (dialkylamino)dimethylsilanes gave tertiary amines in moderate to high yields. The reductive amination of aliphatic aldehydes was effectively catalyzed by ZnI2. Methyl
