51227-15-7Relevant 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.
Practical access to amines by platinum-catalyzed reduction of carboxamides with hydrosilanes: Synergy of dual Si-H groups leads to high efficiency and selectivity
Hanada, Shiori,Tsutsumi, Emi,Motoyama, Yukihiro,Nagashima, Hideo
supporting information; experimental part, p. 15032 - 15040 (2010/01/29)
The synergetic effect of two Si-H groups leads to efficient reduction of carboxamides to amines by platinum catalysts under mild conditions. The rate of the reaction is dependent on the distance of two Si-H groups; 1,1,3,3-tetramethyldisiloxane (TMDS) and 1,2-bis(dimethylsilyl)benzene are found to be an effective reducing reagent. The reduction of amides having other reducible functional groups such as NO2, CO2R, CN, CdC, Cl, and Br moieties proceeds with these groups remaining intact, providing a reliable method for the access to functionalized amine derivatives. The platinum-catalyzed reduction of amides with polymethylhydrosiloxane (PMHS) also proceeds under mild conditions. The reaction is accompanied by automatic removal of both platinum and silicon wastes as insoluble silicone resin, and the product is obtained by simple extraction. A mechanism involving double oxidative addition of TMDS to a platinum center is discussed.
Dual Si-H effects in platinum-catalyzed silane reduction of carboxamides leading to a practical synthetic process of tertiary-amines involving self-encapsulation of the catalyst species into the insoluble silicone resin formed
Hanada, Shiori,Motoyama, Yukihiro,Nagashima, Hideo
, p. 6173 - 6177 (2007/10/03)
Combination of commercially available platinum catalysts with siloxanes containing more than two Si-H groups is found to be an efficient catalyst system for the reduction of carboxamides to amines. In particular, facile removal of silicon and platinum residues from the product can be achieved by the use of polymethylhydrosiloxanes as reducing reagents.
