698-00-0Relevant articles and documents
Mesoionic N-heterocyclic olefin catalysed reductive functionalization of CO2for consecutiveN-methylation of amines
Das, Arpan,Maji, Subir,Mandal, Swadhin K.
, p. 12174 - 12180 (2021/09/28)
A mesoionic N-heterocyclic olefin (mNHO) was introduced as a metal-free catalyst for the reductive functionalization of CO2leading to consecutive doubleN-methylation of primary amines in the presence of 9-borabicyclo[3.3.1]nonane (9-BBN). A wide range of secondary amines and primary amines were successfully methylated under mild conditions. The catalyst sustained over six successive cycles ofN-methylation of secondary amines without compromising its activity, which encouraged us to check its efficacy towards doubleN-methylation of primary amines. Moreover, this method was utilized for the synthesis of two commercially available drug molecules. A detailed mechanistic cycle was proposed by performing a series of control reactions along with the successful characterisation of active catalytic intermediates either by single-crystal X-ray study or by NMR spectroscopic studies in association with DFT calculations.
Dirhodium-Catalyzed Chemo-and Site-Selective C-H Amidation of N, N-Dialkylanilines
Chen, Gong,Arai, Kenta,Morisaki, Kazuhiro,Kawabata, Takeo,Ueda, Yoshihiro
supporting information, p. 728 - 732 (2021/01/18)
A method for dirhodium-catalyzed C(sp 3)-H amidation of N, N-dimethylanilines was developed. Chemoselective C(sp 3)-H amidation of N-methyl group proceeded exclusively in the presence of C(sp 2)-H bonds of the electron-rich aromatic ring. Site-selective C(sp 3)-H amidation proceeded exclusively at the N-methyl group of N-methyl-N-Alkylaniline derivatives with secondary, tertiary, and benzylic C(sp 3)-H bonds α to a nitrogen atom.
Synergistic catalysis of Cu+/Cu0 for efficient and selective N-methylation of nitroarenes with para-formaldehyde
Dong, Xiaosu,Wang, Zhaozhan,Yuan, Youzhu,Yang, Yong
, p. 304 - 313 (2019/07/02)
In this paper, an inexpensive heterogeneous copper nanoparticles catalyst derived from CuAl-layered double hydroxide via an in situ topotactic transformation process was developed. Cu nanoparticles with uniform size were homogeneously dispersed on amorphous Al2O3 with strong metal-support interaction. Characterization results reveals that the Cu0 and Cu+ were simultaneously formed with Cu+ species as the dominant sites on the surface during the reduction process. The resultant catalyst Cu/Al2O3 demonstrates high catalytic activity, selectivity and durability for the reductive N-methylation of easily available nitroarenes in a cost-efficient, environmentally friendly and cascade manner. A broad spectrum of nitroarenes could be efficiently N-methylated to their corresponding N,N-dimethyl amines with good compatibility of various functional groups. The protocol is also applicable for the late-stage functionalization of biologically and pharmaceutically active nitro molecules. A structure-function relationship discloses that Cu0 and Cu+ sites on the surface pronouncedly boosts the reaction efficiency in a synergistic manner, in which Cu0 could facilitate H2 production and N-methylation of anilines, while Cu+ is considerably more active and participates in the overall process of the selective N-methylation of nitroarenes. Moreover, the catalyst also showed a strong stability and could be easily separated for successive reuses without an appreciable loss in activity and selectivity.
Atom-Economic Electron Donors for Photobiocatalytic Halogenations
Seel, Catharina Julia,Králík, Antonín,Hacker, Melanie,Frank, Annika,K?nig, Burkhard,Gulder, Tanja
, p. 3960 - 3963 (2018/09/25)
In vitro cofactor supply and regeneration have been a major obstacle for biocatalytic processes, in particular on a large scale. Peroxidases often suffer from inactivation by their oxidative co-factor. Combining photocatalysis and biocatalysis offers an innovative solution to this problem, but lacks atom economy due to the sacrificial electron donors needed. Herein, we show that redox-active buffers or even water alone can serve as efficient, biocompatible electron sources, when combined with photocatalysis. Mechanistic investigations revealed first insights into the possibilities and limitations of this approach and allowed adjusting the reaction conditions to the specific needs of biocatalytic transformations. Proof-of-concept for the applicability of this photobiocatalytic reaction setup was given by enzymatic halogenations.
2-[(2-dimethylaminophenyl)(phenyl)phosphino]-N,N-dimethylaniline copper iodide complex and synthesis method thereof
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Paragraph 0011-0012; 0034-0036; 0038, (2018/10/11)
The invention relates to a 2-[(2-dimethylaminophenyl)(phenyl)phosphino]-N,N-dimethylaniline copper iodide complex and a synthesis method and the application thereof. The synthesis method comprises thefollowing steps: firstly, enabling 2-bromoaniline and m
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.
Gold-Catalyzed Reductive Transformation of Nitro Compounds Using Formic Acid: Mild, Efficient, and Versatile
Yu, Lei,Zhang, Qi,Li, Shu-Shuang,Huang, Jun,Liu, Yong-Mei,He, He-Yong,Cao, Yong
, p. 3029 - 3035 (2015/09/28)
Developing new efficient catalytic systems to convert abundant and renewable feedstocks into valuable products in a compact, flexible, and target-specific manner is of high importance in modern synthetic chemistry. Here, we describe a versatile set of mild catalytic conditions utilizing a single gold-based solid catalyst that enables the direct and additive-free preparation of four distinct and important amine derivatives (amines, formamides, benzimidazoles, and dimethlyated amines) from readily available formic acid (FA) and nitro starting materials with high level of chemoselectivity. By controlling the stoichiometry of the employed FA, which has attracted considerable interest in the area of sustainable chemistry because of its potential as an entirely renewable hydrogen carrier and as a versatile C1 source, a facile atom- and step-efficient transformation of nitro compounds can be realized in a modular fashion. Renewable formic acid as a flexible feedstock: A versatile heterogeneous gold-based catalytic system has been developed for the controlled, flexible, and target-specific reductive transformation of nitro compounds using stoichiometric equivalents of formic acid as a key starting material under mild and convenient conditions. The overall operational simplicity, high chemoselectivity, functional-group tolerance, and reusability of the catalyst make this approach an attractive and reliable tool for organic and process chemists.
Sono-bromination of aromatic compounds based on the ultrasonic advanced oxidation processes
Fujita, Mitsue,Lévêque, Jean-Marc,Komatsu, Naoki,Kimura, Takahide
, p. 247 - 251 (2015/06/08)
A novel, mild "sono-halogenation" of various aromatic compounds with potassium halide was investigated under ultrasound in a biphasic carbon tetrachloride/water medium. The feasibility study was first undertaken with the potassium bromide and then extended to chloride and iodide analogues. This methodology could be considered as a new expansion of the ultrasonic advanced oxidation processes (UAOPs) into a synthetic aspect as the developed methodology is linked to the sonolytic disappearance of carbon tetrachloride. Advantages of the present method are not only that the manipulation of the bromination is simple and green, but also that the halogenating agents used are readily available, inexpensive, and easy-handling.
Direct oxidative cyanation of tertiary amines promoted by in situ generated hypervalent iodine(III)-CN intermediate
Shen, Hang,Zhang, Xiaohui,Liu, Qing,Pan, Jing,Hu, Wen,Xiong, Yan,Zhu, Xiangming
supporting information, p. 5628 - 5631 (2015/09/21)
An environmentally benign and metal-free cyanation method of tertiary amines oxidated by hypervalent iodine(III) intermediate generated in situ from PIFA (or DIB) and TMSCN has been developed. A variety of substituent groups on amines are tolerated to the oxidation of α-C-H bond to form C-C bond in the absence of metal catalysts with yields of up to 74%.
Metal-free functionalization of N, N-dialkylanilines via temporary oxidation to N, N-dialkylaniline N-oxides and group transfer
Lewis, Robert S.,Wisthoff, Michael F.,Grissmerson,Chain, William J.
supporting information, p. 3832 - 3835 (2014/08/05)
A simple set of protocols for the controlled elaboration of anilines is reported allowing access to a diverse array of aminophenols, aminoarylsulfonates, alkylated anilines, and aminoanilines in 29-95% yield in a single laboratory operation from easily isolable, bench-stable N,N-dialkylaniline N-oxides. The introduction of new C-O, C-C, and C-N bonds on the aromatic ring is made possible by a temporary increase in oxidation level and excision of a weak N-O bond.
