94-34-8Relevant articles and documents
Bio-heterogeneous Cu(0)NC@PHA for n-aryl/alkylation at room temperature
Jian Fui, Choong,Lutfor Rahman, Md,Musta, Baba,Sani Sarjadi, Mohd,Sarkar, Shaheen M.,Xin Ting, Tang
, (2021/06/28)
A pure cellulose was derived from waste fibre and it was chemically modified to a hydroxamic acid ligand. The poly(hydroxamic acid) was treated with an aqueous copper solution to afford the greenish stable five-membered copper complex; namely Cu(II)@PHA. Further, the Cu(II)@PHA was treated with a reducing agent hydrazine hydride to give brown colour cellulose supported copper nanocomplex (Cu(0)NC@PHA). The Cu(0)NC@PHA was characterised by ATR-FTIR, FE-SEM & EDS, TEM, ICP-OES, TGA, XRD and XPS analyses. The cellulose-based Cu(0)NC@PHA was used for the n-aryl/alkylation (Michael addition) reaction with a variety of α,β-unsaturated Michael acceptors to produce the corresponding n-aryl/alkyl products with an excellent yield at room temperature. The Cu(0)NC@PHA showed extraordinary stability and it was easily filtered out from the reaction mixture and may potentially recycled up to five times without loss of its original catalytic ability.
Air-tolerant direct reductive N-methylation of amines using formic acid via simple inorganic base catalysis
Huang, Yan,Deng, Wei,Lin, Bo-Lin
supporting information, (2019/05/29)
The construction of N-methyl amine moieties is an important reaction that has found numerous applications. Development of new methylation agents that are more environmentally benign than classical agents, such as iodomethane and methyl sulfate, is still highly desirable. Herein, we report a convenient protocol for direct reductive N-methylation of amines using formic acid as the methylation agent via simple inorganic base catalysis. The present protocol operates under transition-metal-free and air-tolerant conditions. Both the catalyst, K2HPO4, and the reductant, polymethylhydrosiloxane (PMHS), are cheap and easily separable from the crude reaction product mixture. Mechanistic investigations suggest that the reaction occur through the formation of an acetal intermediate followed by the C–N bond formation.
Preparation method by using amine and imine nitrogen methylation and application thereof
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Paragraph 0165; 0166; 0167; 0168; 0169; 0170, (2017/08/10)
The invention discloses a preparation method by using amine and imine nitrogen methylation and application thereof. The preparation method comprises the following steps: A, adding an active carbon loaded platinum catalyst into a Schlenk tube, and after vacuumizing to replace argon, adding a solvent; B, under protection of argon, separately adding phenylsilane, an initial raw material and formic acid; C, stirring the whole reaction system at a certain temperature to react; and D, after reaction, adding ethyl acetate into the system to dilute, stopping the reaction by using a sodium hydroxide aqueous solution, performing extraction with ethyl acetate, separating out an organic phase, drying and filtering the organic phase, and performing rotatable evaporation to remove the solvent. Column chromatography is performed on residues by using ethyl acetate/petroleum ether mixed solvent to obtain a target product, wherein the ethyl acetate and petroleum ether are different in proportion. According to the application of the method in isotope labeled drug synthesis, the dosage of a catalyst is extremely low, the cost is quite low, and the method is suitable for large-scaled production, can be suitable for amine and imine with different substituents, and suitable for realizing methylation conveniently on nitrogen atoms in a natural product structure to prepare drug molecules.
