33863-79-5Relevant academic research and scientific papers
Photocatalytic Water-Splitting Coupled with Alkanol Oxidation for Selective N-alkylation Reactions over Carbon Nitride
Xu, Yangsen,Zhang, Zhaofei,Qiu, Chuntian,Chen, Shaoqin,Ling, Xiang,Su, Chenliang
, p. 582 - 589 (2020/12/09)
Photocatalytic water splitting technology (PWST) enables the direct use of water as appealing “liquid hydrogen source” for transfer hydrogenation reactions. Currently, the development of PWST-based transfer hydrogenations is still in an embryonic stage. Previous reports generally centered on the rational utilization of the in situ generated H-source (electrons) for hydrogenations, in which photogenerated holes were quenched by sacrificial reagents. Herein, the fully-utilization of the liquid H-source and holes during water splitting is presented for photo-reductive N-alkylation of nitro-aromatic compounds. In this integrate system, H-species in situ generated from water splitting were designed for nitroarenes reduction to produce amines, while alkanols were oxidized by holes for cascade alkylating of anilines as well as the generated secondary amines. More than 50 examples achieved with a broad range scope validate the universal applicability of this mild and sustainable coupling approach. The synthetic utility of this protocol was further demonstrated by the synthesis of existing pharmaceuticals via selective N-alkylation of amines. This strategy based on the sustainable water splitting technology highlights a significant and promising route for selective synthesis of valuable N-alkylated fine chemicals and pharmaceuticals from nitroarenes and amines with water and alkanols.
New benzamide derivatives and their nicotinamide/cinnamamide analogs as cholinesterase inhibitors
Bilginer, Sinan,Koca, Mehmet
, (2021/06/30)
In this study, a total of 18 new benzamide/ nicotinamide/ cinnamamide derivative compounds were designed and synthesized for the first time (except B1 and B5) by conventional and microwave irradiation methods. The chemical structures of the synthesized co
Manganese-Catalyzed Transfer Hydrogenation of Aldimines
Wei, Duo,Bruneau-Voisine, Antoine,Dubois, Maxime,Bastin, Stéphanie,Sortais, Jean-Baptiste
, p. 5256 - 5259 (2019/04/17)
The reduction of imines to amines via transfer hydrogenation was achieved promoted by phosphine-free manganese(I) catalyst. Using isopropanol as reductant, in the presence of tBuOK (4 mol %) and manganese complex [Mn(CO)3Br(κ2N,N-PyCH2NH2)] (2 mol %), a large variety of aldimines (30 examples) were typically reduced in 3 hours at 80 °C with good to excellent yield.
Application of a catalyst-free Domino Mannich/Friedel-Crafts alkylation reaction for the synthesis of novel tetrahydroquinolines of potential antitumor activity
Castillo, Juan-Carlos,Jiménez, Elizabeth,Portilla, Jaime,Insuasty, Braulio,Quiroga, Jairo,Moreno-Fuquen, Rodolfo,Kennedy, Alan R.,Abonia, Rodrigo
, p. 932 - 947 (2018/02/09)
A useful and efficient method to construct diversely substituted 1,2,3,4-tetrahydroquinolines in good to excellent yields has been developed through a catalyst-free Domino Mannich and intramolecular Friedel-Crafts alkylation reactions of N-arylamines with
Expedient Synthesis of N-Methyl- and N-Alkylamines by Reductive Amination using Reusable Cobalt Oxide Nanoparticles
Senthamarai, Thirusangumurugan,Murugesan, Kathiravan,Natte, Kishore,Kalevaru, Narayana V.,Neumann, Helfried,Kamer, Paul C. J.,Jagadeesh, Rajenahally V.
, p. 1235 - 1240 (2018/02/09)
N-Methyl- and N-alkylamines represent important fine and bulk chemicals that are extensively used in both academic research and industrial production. Notably, these structural motifs are found in a large number of life-science molecules and play vital roles in regulating their activities. Therefore, the development of convenient and cost-effective methods for the synthesis and functionalization of amines by using earth-abundant metal-based catalysts is of scientific interest. In this regard, herein we report an expedient reductive amination process for the selective synthesis of N-methylated and N-alkylated amines by using nitrogen-doped, graphene-activated nanoscale Co3O4-based catalysts. Starting from inexpensive and easily accessible nitroarenes or amines and aqueous formaldehyde or aldehydes in the presence of formic acid, this cost-efficient reductive amination protocol allows the synthesis of various N-methyl- and N-alkylamines, amino acid derivatives, and existing drug molecules.
Synthesis of secondary amines by reductive amination of aldehydes with nitroarenes over supported copper catalysts in a flow reactor
Nuzhdin, Alexey L.,Artiukha, Ekaterina A.,Bukhtiyarova, Galina A.,Derevyannikova, Elizaveta A.,Bukhtiyarov, Valerii I.
, p. 108 - 113 (2017/09/15)
Supported copper catalysts were investigated for the one-pot reductive amination of aldehydes with nitroarenes in a continuous flow reactor. This process is considered advantageous compared to current traditional methods, which present several drawbacks, such as toxicity of reducing or alkylation agent, lack of monoalkylation selectivity and large amounts of waste produced. Various secondary amines were synthesized in good to excellent yields in the reactions of aliphatic aldehydes with nitroarenes using molecular hydrogen as a reducing agent. It was found that the yield of secondary amine depends on the rate of formation of intermediate imine.
Flow synthesis of secondary amines over Ag/Al2O3 catalyst by one-pot reductive amination of aldehydes with nitroarenes
Artiukha, Ekaterina A.,Nuzhdin, Alexey L.,Bukhtiyarova, Galina A.,Bukhtiyarov, Valerii I.
, p. 45856 - 45861 (2017/10/06)
An alumina-supported silver catalyst was investigated in the one-pot reductive amination of aldehydes with nitroarenes in a continuous flow reactor using molecular hydrogen as a reducing agent. A series of secondary amines containing alkyl, OH, OCH3, Cl, Br and CC groups was synthesized in good to excellent yields. The yield of the secondary amine depends on the rate of formation of an intermediate imine. It was shown that the accumulation of carbonaceous deposits on the catalyst is the main reason of catalyst deactivation. The spent catalyst can be easily regenerated and reused without losing catalytic activity.
Co(II) PCP Pincer Complexes as Catalysts for the Alkylation of Aromatic Amines with Primary Alcohols
Mastalir, Matthias,Tomsu, Gerald,Pittenauer, Ernst,Allmaier, Günter,Kirchner, Karl
supporting information, p. 3462 - 3465 (2016/07/26)
Efficient alkylations of amines by alcohols catalyzed by well-defined Co(II) complexes are described that are stabilized by a PCP ligand (N,N′-bis(diisopropylphosphino)-N,N′-dimethyl-1,3-diaminobenzene) based on the 1,3-diaminobenzene scaffold. This reaction is an environmentally benign process implementing inexpensive, earth-abundant nonprecious metal catalysts and is based on the acceptorless alcohol dehydrogenation concept. A range of primary alcohols and aromatic amines were efficiently converted into mono-N-alkylated amines in good to excellent isolated yields.
Air Stable Iron(II) PNP Pincer Complexes as Efficient Catalysts for the Selective Alkylation of Amines with Alcohols
Mastalir, Matthias,St?ger, Berthold,Pittenauer, Ernst,Puchberger, Michael,Allmaier, Günter,Kirchner, Karl
, p. 3824 - 3831 (2016/12/16)
A series of well-defined iron(II) complexes of the types [Fe(PNP)Br2] and [Fe(PNP)(CO)Br2] with PNP pincer ligands based on triazine and pyridine backbones were prepared and fully characterized. These complexes were tested as catalysts for the alkylation of amines by alcohols. The high-spin complexes [Fe(PNP)Br2] are catalytically inactive. The low-spin complexes [Fe(PNP)(CO)Br2] bearing a carbonyl co-ligand efficiently and selectively convert primary alcohols and aromatic and benzylic amines selectively into mono-N-alkylated amines in good to excellent isolated yields. A mechanistic proposal is given. (Figure presented.).
A Highly Efficient Base-Metal Catalyst: Chemoselective Reduction of Imines to Amines Using An Abnormal-NHC-Fe(0) Complex
Bhunia, Mrinal,Hota, Pradip Kumar,Vijaykumar, Gonela,Adhikari, Debashis,Mandal, Swadhin K.
supporting information, p. 2930 - 2937 (2016/10/06)
A base-metal, Fe(0)-catalyzed hydrosilylation of imines to obtain amines is reported here which outperforms its noble-metal congeners with the highest TON of 17000. The catalyst, (aNHC)Fe(CO)4, works under very mild conditions, with extremely low catalyst loading (down to 0.005 mol %), and exhibits excellent chemoselectivity. The facile nature of the imine reduction under mild conditions has been further demonstrated by reducing imines towards expensive commercial amines and biologically important N-alkylated sugars, which are difficult to achieve otherwise. A mechanistic pathway and the source of chemoselectivity for imine hydrosilylation have been proposed on the basis of the well-defined catalyst and isolable intermediates along the catalytic cycle.
