611-21-2Relevant articles and documents
Method for realizing N-alkylation by using alcohols as carbon source under photocatalysis
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Paragraph 0048-0057, (2021/03/13)
The invention discloses a method for realizing N-alkylation by using alcohols as a carbon source under photocatalysis, and belongs to the technical field of catalytic synthesis. Alcohol, a substrate raw material and a catalyst are placed in a reaction device, ultraviolet and/or visible light irradiation is carried out in an inert atmosphere, after the irradiation is finished, solid-liquid separation is carried out to remove the catalyst, and an N-alkylation product can be obtained through extraction, distillation and purification, wherein the substrate raw material comprises any one of an amine compound, an aromatic nitro compound or an aromatic nitrile compound, the alcohol comprises any one or more of soluble primary alcohols, and the catalyst is metal oxide/titanium dioxide or metal sulfide/titanium dioxide. The method is simple and easy to operate, can be used for efficient photocatalysis one-pot multi-step hydrogenation N-alkylation reaction, and is mild in reaction condition, high in chemical selectivity of N-alkylamine, good in catalyst stability and easy to recycle.
Effect of the ancillary ligand in N-heterocyclic carbene iridium(III) catalyzed N-alkylation of amines with alcohols
Feng, Xinshu,Huang, Ming
, (2021/06/21)
A series of air-stable N-heterocyclic carbene (NHC) Ir(III) complexes (Ir1-6), bearing various combinations of chlorine, pyridine and NHC ligands, were assayed for the N-alkylation of amines with alcohols. It was found that Ir3, with two monodentate 1,3-bis-methyl-imidazolylidene (IMe) ligands, emerged as the most active complex. A large variety of amines and primary alcohols were efficiently converted into mono-N-alkylated amines in 53–96% yields. As a special highlight, for the challenging MeOH, selective N-monomethylation could be achieved using KOH as a base under an air atmosphere. Moreover, this catalytic system was successfully applied to the gram-scale synthesis of some valuable compounds.
Efficient methylation of anilines with methanol catalysed by cyclometalated ruthenium complexes
Piehl, Patrick,Amuso, Roberta,Spannenberg, Anke,Gabriele, Bartolo,Neumann, Helfried,Beller, Matthias
, p. 2512 - 2517 (2021/04/22)
Cyclometalated ruthenium complexes4-10allow the effective methylation of anilines with methanol to selectively giveN-methylanilines. This hydrogen autotransfer procedure proceeds under mild conditions (60 °C) in a practical manner (NaOH as base). Mechanistic investigations suggest an active homogenous ruthenium complex and β-hydride elimination of methanol as the rate determining step.
Synthesis of N-Alkyl Anilines from Arenes via Iron-Promoted Aromatic C-H Amination
Falk, Eric,Gasser, Valentina C. M.,Morandi, Bill
supporting information, p. 1422 - 1426 (2021/03/08)
We report both an intermolecular C-H amination of arenes to access N-methylanilines and an intramolecular variant for the synthesis of tetrahydroquinolines. A newly developed, highly electrophilic aminating reagent was key for the direct synthesis of unprotected N-methylanilines from simple arenes. The reactions display a broad functional group tolerance and employ catalytic amounts of a benign iron salt under mild reaction conditions.
CO2-tuned highly selective reduction of formamides to the corresponding methylamines
Chao, Jianbin,Guo, Zhiqiang,Pang, Tengfei,Wei, Xuehong,Xi, Chanjuan,Yan, Leilei
supporting information, p. 7534 - 7538 (2021/10/12)
We herein describe an efficient, CO2-tuned and highly selective C-O bond cleavage of N-methylated formanilides. With easy-to-handle and commercially available NaBH4 as the reductant, a variety of formanilides could be turned into the desired tertiary amines in moderate to excellent yields. The role of CO2 has been investigated in detail, and the mechanism is proposed on the basis of experiments.
Photon-initiated heterogeneous redox couples for methylation of anilines under mild conditions
Zhang, Bing,Gao, Hua,Wang, Wei
, p. 4433 - 4437 (2020/08/10)
Methylation of anilines has drawn a lot of attention due to their valuable applications and directly using methanol as a methylation reagent is of great advantage. Photon-initiated heterogeneous catalysis of this methylation process meets the requirements of green chemistry. Herein we show that balanced redox zones within carbon nitride supported Pd nanoparticles boost the selectivity of methylation of anilines under mild conditions.
Selective mono-N-methylation of nitroarenes with methanol catalyzed by atomically dispersed NHC-Ir solid assemblies
Chen, Jiangbo,Chen, Zhe-Ning,Tu, Tao,Wang, Jiaquan,Wen, Daheng,Wu, Jiajie,Xu, Xin,Zheng, Qingshu
, p. 337 - 344 (2020/07/03)
A series of N-heterocyclic carbene-iridium (NHC-Ir) coordination assemblies based on bis-pyrenoimidazolium salts are prepared, and shown to function as efficient solid molecular catalysts in selective mono-N-methylation of nitroarenes with methanol under mild conditions. The atomically dispersed active Ir(I) centers and the large π-conjugation rings endow the solid catalysts with an exceptionally high activity and selectivity for a broad substrate scope. Such solid NHC-Ir coordination assemblies are robust, which can be easily recovered and reused more than 10 runs without significant loss of their catalytic activity and selectivity. When combined with a subsequent formylation using the same solid catalysts under ambient conditions, this novel protocol can afford diverse formamides in excellent yields, further highlighting the applicability of the present solid catalysts for an efficient diversification of nitroarenes to a broad number of functional amines.
Selective Pd-catalyzed monoarylation of small primary alkyl amines through backbone-modification in ylide-functionalized phosphines (YPhos)
Rodstein, Ilja,Prendes, Daniel Sowa,Wickert, Leon,Paa?en, Maurice,Gessner, Viktoria H.
, p. 14674 - 14683 (2020/12/29)
Ylide-substituted phosphines have been shown to be excellent ligands for C-N coupling reactions under mild reaction conditions. Here we report studies on the impact of the steric demand of the substituent in the ylide-backbone on the catalytic activity. Two new YPhos ligands with bulky ortho-tolyl (pinkYPhos) and mesityl (mesYPhos) substituents were synthesized, which are slightly more sterically demanding than their phenyl analogue but considerably less flexible. This change in the ligand design leads to higher selectivities and yields in the arylation of small primary amines compared to previously reported YPhos ligands. Even MeNH2 and EtNH2 could be coupled at room temperature with a series of aryl chlorides in high yields.
P(III)/P(V)-Catalyzed Methylamination of Arylboronic Acids and Esters: Reductive C-N Coupling with Nitromethane as a Methylamine Surrogate
Li, Gen,Qin, Ziyang,Radosevich, Alexander T.
supporting information, p. 16205 - 16210 (2020/10/26)
The direct reductive N-arylation of nitromethane by organophosphorus-catalyzed reductive C-N coupling with arylboronic acid derivatives is reported. This method operates by the action of a small ring organophosphorus-based catalyst (1,2,2,3,4,4-hexamethylphosphetane P-oxide) together with a mild terminal reductant hydrosilane to drive the selective installation of the methylamino group to (hetero)aromatic boronic acids and esters. This method also provides for a unified synthetic approach to isotopically labeled N-methylanilines from various stable isotopologues of nitromethane (i.e., CD3NO2, CH315NO2, and 13CH3NO2), revealing this easy-to-handle compound as a versatile precursor for the direct installation of the methylamino group.
Selective N -monomethylation of primary anilines with the controllable installation of N -CH2D, N -CHD2, and N -CD3units
Meng, Jing,Wang, Yi-Feng,Wang, Zhijuan,Xia, Hui-Min,Xu, Ai-Qing,Zhang, Feng-Lian
supporting information, p. 4922 - 4926 (2020/07/30)
The selective N-monomethylation of primary anilines was realized by the use of the Me3N-BH3/N,N-dimethylformamide (DMF) system as the methyl source. This method also allows for the controllable introduction of N-CH2D, N-CHD2, and N-CD3 units with high lev
