72753-31-2Relevant academic research and scientific papers
Tungsten-Catalyzed Direct N-Alkylation of Anilines with Alcohols
Lan, Xiao-Bing,Ye, Zongren,Yang, Chenhui,Li, Weikang,Liu, Jiahao,Huang, Ming,Liu, Yan,Ke, Zhuofeng
, p. 860 - 865 (2021/01/18)
The implementation of non-noble metals mediated chemistry is a major goal in homogeneous catalysis. Borrowing hydrogen/hydrogen autotransfer (BH/HA) reaction, as a straightforward and sustainable synthetic method, has attracted considerable attention in the development of non-noble metal catalysts. Herein, we report a tungsten-catalyzed N-alkylation reaction of anilines with primary alcohols via BH/HA. This phosphine-free W(phen)(CO)4 (phen=1,10-phenthroline) system was demonstrated as a practical and easily accessible in-situ catalysis for a broad range of amines and alcohols (up to 49 examples, including 16 previously undisclosed products). Notably, this tungsten system can tolerate numerous functional groups, especially the challenging substrates with sterically hindered substituents, or heteroatoms. Mechanistic insights based on experimental and computational studies are also provided.
Convenient and Reusable Manganese-Based Nanocatalyst for Amination of Alcohols
Subaramanian, Murugan,Ramar, Palmurukan M.,Sivakumar, Ganesan,Kadam, Ravishankar G.,Petr, Martin,Zboril, Radek,Gawande, Manoj B.,Balaraman, Ekambaram
, p. 4334 - 4341 (2021/08/25)
The development of new sustainable nanocatalytic systems for green chemical synthesis is a growing area in chemical science. Herein, a reusable heterogeneous N-doped graphene-based manganese nanocatalyst (Mn@NrGO) for selective N-alkylation of amines with alcohols is described. Mechanistic studies illustrate that the catalytic reaction follows a domino dehydrogenation-condensation-hydrogenation sequence of alcohols and amines with the formation of water as the sole by-product. The scope of the reaction is extended to the synthesis of pharmaceutically important N-alkylated amine intermediates. The heterogeneous nature of the catalyst made it easy to separate for long-term performance, and the recycling study revealed that the catalyst was robust and retained its activity after several recycling experiments.
Scalable synthesis of secondary and tertiary amines by heterogeneous Pt-Sn/γ-Al2O3catalyzed N-alkylation of amines with alcohols
Wu, Kaikai,He, Wei,Sun, Chenglin,Yu, Zhengkun
supporting information, p. 8516 - 8521 (2016/11/28)
Synthesis of secondary and tertiary amines has been efficiently realized from the N-alkylation of amines with alcohols by means of heterogeneous bimetallic Pt-Sn/γ-Al2O3catalyst (0.5?wt % Pt, molar ratio Pt:Sn?=?1:3) through a borrowing hydrogen strategy. The Pt-Sn/γ-Al2O3catalyst has exhibited very high catalytic activity towards a wide range of amines and alcohols, and can be conveniently recycled without Pt metal leaching. The present protocol was applied for the synthesis of N-phenylbenzylamine in 96% isolated yield from aniline and benzyl alcohol on a 2.1?kg scale of the substrates, demonstrating its potential applicability for higher-order amine synthesis.
Transfer hydrogenative reductive amination of aldehydes in aqueous sodium formate solution
Zhu, Mengping
, p. 509 - 511 (2016/01/12)
A practical direct reductive amination reaction of aldehydes in aqueous sodium formate solution which produces amines in good yields under mild conditions is described. The amount and strength of the acid additives were critical factors to affect the reaction selectivities. This reductive amination method has great application potential for the synthesis of amine products given the mild conditions, short reaction time, the use of water as a solvent, and the use of benign hydrogen sources.
Nano-sized NiLa2O4 spinel-NaBH4-mediated reduction of imines to secondary amines
Shiri, Ali,Soleymanpour, Faezehy,Eshghi, Hossein,Khosravi, Iman
, p. 1191 - 1196 (2015/09/01)
Nano-sized NiLa2O4 spinel was produced by thermal decomposition of Ni-La compounds via a sol-gel method. The well-crystallized spinel structure was formed after calcination at 750 °C. The physicochemical properties of the spinel were investigated using differential thermal analysis, X-ray diffraction, transmission electron microscopy, scanning electron microscopy, and particle size distribution analysis. The results show that the nanoparticles have regular shapes with well-defined crystal faces and consist of uniform quasi-spherical crystallites of average size 40 nm. The refined unit cell parameters are a = 3.861205 ? and c = 12.6793 ?. This new nano-sized NiLa2O4 spinel is an efficient heterogeneous catalyst for the selective conversion of imines to the corresponding secondary amines in the presence of NaBH4 as a reducing agent, in good to excellent yields. All the reactions were completely chemoselective at room temperature and had relatively short reaction times. Secondary amines with different aryl groups, including those bearing electron-withdrawing or electron-donating groups, were obtained under the optimum reaction conditions. The catalyst was readily recovered and was recycled four times with no significant loss of catalytic activity.
Ruthenium-catalyzed direct reductive amination in HCOOH/NEt3 mixture
Zhu, Mengping
, p. 1568 - 1572,5 (2014/10/15)
A one-pot direct reductive amination of aldehydes with primary and secondary amines using Noyori's catalyst (η 6-arene)Ru(H)TsDPEN in neat HCOOH/NEt3 mixture has been developed. The catalyst formed in situ allows full conversion of aldehydes with high selectivities towards the desired amine products within hours or even minutes at room temperature. For aromatic aldehydes, both 5:2 and 5:3 HCOOH/NEt3 mixtures prove to be suitable reaction media, with the former affording higher selectivities while the latter leading to much faster reaction rates. For aliphatic aldehydes, the 5:3 HCOOH/NEt3 mixture gives much higher selectivities due to the minimal loss from aldol condensation. This method has great application potential for the synthesis of amine products given the mild conditions. Graphical Abstract: [Figure not available: see fulltext.]
Synthesis and anticholinesterase activity of fumaramide derivatives
Yerdelen, Kadir Ozden,Gul, Halise Inci
, p. 4920 - 4929 (2013/09/23)
A series of fumaramide derivatives were synthesized from substituted benzanilines and their cholinesterase inhibitory activity was assayed according to Ellman's method using galanthamine-HBr as the reference compound. Most of the fumaramide compounds showed inhibitory activity of both cholinesterase enzymes. Compounds 29 (IC50 = 0.14 μM) and 30 (IC50 = 16.50 μM) were found to be the most active inhibitors on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes, respectively. Molecular docking studies were performed with Surflex-Dock programme to provide the possible interactions between compounds and enzymes. A Lineweaver-Burk plot and molecular modelling studies showed that fumaramide compounds targeted both the catalytic anionic site and the peripheral anionic site of AChE. It was revealed that the nature of α,β-unsaturated 1,4-diketone moiety in fumaramide compounds brought about useful and efficient modification especially on AChE inhibition.
Manganese dioxide catalyzed N-alkylation of sulfonamides and amines with alcohols under air
Yu, Xiaochun,Liu, Chuanzhi,Jiang, Lan,Xu, Qing
supporting information; experimental part, p. 6184 - 6187 (2012/01/06)
By simply running the reactions under air and solvent-free conditions using catalytic amounts of manganese dioxide, a practical and efficient N-alkylation method for a variety of sulfonamides and amines using alcohols as green alkylating reagents was developed.
Discovery and mechanistic studies of a general air-promoted metal-catalyzed aerobic n- alkylation reaction of amides and amines with alcohols
Liu, Chuanzhi,Liao, Shiheng,Li, Qiang,Feng, Sunlin,Sun, Qing,Yu, Xiaochun,Xu, Qing
supporting information; scheme or table, p. 5759 - 5773 (2011/09/16)
The thermodynamically unfavorable anaerobic dehydrogenative alcohol activation to aldehydes and hydridometal species is found to be the bottleneck in metal-catalyzed N-alkylations due to a general and unnoticed catalyst deactivation by amines/amides. Thus, different from the anaerobic dehydrogenation process in borrowing hydrogen or hydrogen autotransfer reactions that require noble metal complexes or addition of capricious ligands for catalyst activation, the water-producing, exothermic, metal-catalyzed aerobic alcohol oxidation is thermodynamically more favorable and the most effective and advantageous aldehyde generation protocol. This leads to a general and advantageous air-promoted metal-catalyzed aerobic N-alkylation methodology that effectively uses many simpler, less expensive, more available, and ligand-free metal catalysts that were inactive under typical anaerobic borrowing hydrogen conditions, avoiding the use of preformed metal complexes and activating ligands and the exclusive requirement of inert atmosphere protection. This aerobic method is quite general in substrate scope and tolerates various amides, amines, and alcohols, revealing its potentially broad utilities and interests in academy and industry. In contrast to the commonly accepted borrowing hydrogen mechanism, based on a thorough mechanistic study and supported by the related literature background, a new mechanism analogous to the relay race game that has never been proposed in metal-catalyzed N-alkylation reactions is presented.
Catalyst-free one-pot reductive alkylation of primary and secondary amines and N,N-dimethylation of amino acids using sodium borohydride in 2,2,2-trifluoroethanol
Tajbakhsh, Mahmood,Hosseinzadeh, Rahman,Alinezhad, Heshmatollah,Ghahari, Somayeh,Heydari, Akbar,Khaksar, Samad
experimental part, p. 490 - 496 (2011/03/20)
A simple and convenient procedure for the reductive alkylation of primary and secondary amines and N,N-dimethylation of amino acids is described using sodium borohydride as a reducing agent in 2,2,2- trifluoroethanol without use of a catalyst or any other additive. The solvent can be readily recovered from reaction products in excellent purity for direct reuse. Georg Thieme Verlag Stuttgart - New York.
