7396-58-9Relevant articles and documents
Simple RuCl3-catalyzed N-Methylation of Amines and Transfer Hydrogenation of Nitroarenes using Methanol
Sarki, Naina,Goyal, Vishakha,Tyagi, Nitin Kumar,Puttaswamy,Narani, Anand,Ray, Anjan,Natte, Kishore
, p. 1722 - 1729 (2021/04/19)
Methanol is a potential hydrogen source and C1 synthon, which finds interesting applications in both chemical synthesis and energy technologies. The effective utilization of this simple alcohol in organic synthesis is of central importance and attracts scientific interest. Herein, we report a clean and cost-competitive method with the use of methanol as both C1 synthon and H2 source for selective N-methylation of amines by employing relatively cheap RuCl3.xH2O as a ligand-free catalyst. This readily available catalyst tolerates various amines comprising electron-deficient and electron-donating groups and allows them to transform into corresponding N-methylated products in moderate to excellent yields. In addition, few marketed pharmaceutical agents (e. g., venlafaxine and imipramine) were also successfully synthesized via late-stage functionalization from readily available feedstock chemicals, highlighting synthetic value of this advanced N-methylation reaction. Using this platform, we also attempted tandem reactions with selected nitroarenes to convert them into corresponding N-methylated amines using MeOH under H2-free conditions including transfer hydrogenation of nitroarenes-to-anilines and prepared drug molecules (e. g., benzocaine and butamben) as well as key pharmaceutical intermediates. We further enable one-shot selective and green syntheses of 1-methylbenzimidazole using ortho-phenylenediamine (OPDA) and methanol as coupling partners.
Commercial Pd/C-Catalyzed N-Methylation of Nitroarenes and Amines Using Methanol as Both C1 and H2 Source
Goyal, Vishakha,Gahtori, Jyoti,Narani, Anand,Gupta, Piyush,Bordoloi, Ankur,Natte, Kishore
, p. 15389 - 15398 (2019/12/04)
Herein, we report commercially available carbon-supported-palladium (Pd/C)-catalyzed N-methylation of nitroarenes and amines using MeOH as both a C1 and a H2 source. This transformation proceeds with high atom-economy and in an environmentally friendly way via borrowing hydrogen mechanism. A total of >30 structurally diverse N-methylamines, including bioactive compounds, were selectively synthesized with isolated yields of up to 95%. Furthermore, selective N-methylation and deuteration of nimesulide, a nonsteroidal anti-inflammatory drug, were realized through the late-stage functionalization.
TERTIARY AMINE PREPARATION PROCESS
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Paragraph 0104-0106; 0119-0121, (2013/11/06)
The present invention relates to a process for producing a tertiary amine, including the following steps (1) and (2): Step (1); introducing an alcohol having 1 to 36 carbon atoms and a raw amine represented by the following general formula (I) into a first reaction vessel to react with each other in the presence of a catalyst and hydrogen, and then continuing the reaction while discharging water produced in the reaction and a hydrogen-containing gas out of a reaction system in the first reaction vessel: R1R2NH??(I) wherein R1 and R2 are each independently a hydrogen atom or a hydrocarbon group having 1 to 36 carbon atoms; and Step (2): introducing the hydrogen-containing gas discharged from the first reaction vessel into a second reaction vessel to reduce an amount of carbon monoxide contained in the hydrogen-containing gas, and then introducing a part or whole of the hydrogen-containing gas into the first reaction vessel.