83306-62-1Relevant academic research and scientific papers
Copper(i)-catalysed intramolecular hydroarylation-redox cross-dehydrogenative coupling ofN-propargylanilines with phosphites
Li, Guangzhe,Yu, Guo,Wang, Chengdong,Morita, Taiki,Zhang, Xuhai,Nakamura, Hiroyuki
supporting information, p. 113 - 116 (2021/12/29)
Intramolecular hydroarylation-redox cross-dehydrogenative coupling ofN-propargylanilines with phosphite diesters proceeded in the presence of Cu(i)-catalysts (20 mol%) to selectively give 2-phosphono-1,2,3,4-tetrahydroquinolines in good yields with 100% atomic utilization. P-H and two C-H bonds are activated at once and these hydrogen atoms are trapped by a propargylic triple bond in the molecule.
Redox-Neutral Imination of Alcohol with Azide: A Sustainable Alternative to the Staudinger/Aza-Wittig Reaction
Li, Huaifeng,Lupp, Daniel,Das, Pradip K.,Yang, Li,Gon?alves, Théo P.,Huang, Mei-Hui,El Hajoui, Marwa,Liang, Lan-Chang,Huang, Kuo-Wei
, p. 4071 - 4076 (2021/04/12)
The traditional Staudinger/aza-Wittig reaction represents one of the most powerful tools for imine formation. However, for this multistep procedure, the sacrificial phosphine has to be used, resulting in difficulties in the purification process and waste disposal at the same time. Here, we report a redox-neutral azide-alcohol imination methodology enabled by a base-metal nickel PN3 pincer catalyst. The one-step, waste-free, and high atom-economical features highlight its advantages further. Moreover, mechanistic insight suggests a non-metal-ligand cooperation pathway based on the observation of an intermediate and density functional theory calculations.
Ionic-Liquid-Catalyzed Synthesis of Imines, Benzimidazoles, Benzothiazoles, Quinoxalines and Quinolines through C?N, C?S, and C?C Bond Formation
Adimurthy, Subbarayappa,Badhani, Gaurav,Joshi, Abhisek
, p. 6705 - 6716 (2021/12/31)
We report the tetramethyl ammonium hydroxide catalyzed oxidative coupling of amines and alcohols for the synthesis of imines under metal-free conditions by utilizing oxygen from air as the terminal oxidant. Under the same conditions, with ortho-phenylene diamines and 2-aminobenzenethiols the corresponding benzimidazoles and benzothiazoles were obtained. Quinoxalines were obtained from ortho-phenylene diamines and 1-phenylethane-1,2-diol, the conditions were then extended to the synthesis of quinoline building blocks by reaction of 2-amino benzyl alcohols either with 1-phenylethan-1-ol or acetophenone derivatives. The formation of C?N, C?S and C?C bonds was achieved under metal-free conditions. A broad range of amines (aromatic, aliphatic, cyclic and heteroaromatic) as well as benzylic alcohols including heteroaryl alcohols reacted smoothly and provided the desired products. The mild reaction conditions, commercially available catalyst, metal-free, good functional-group tolerance, broad range of products (imines, benzimidazoles, benzothiazoles, quinoxalines and quinolines) and applicability at gram scale reactions are the advantages of the present strategy.
Switchable Imine and Amine Synthesis Catalyzed by a Well-Defined Cobalt Complex
Paudel, Keshav,Xu, Shi,Hietsoi, Oleksandr,Pandey, Bedraj,Onuh, Chuka,Ding, Keying
supporting information, p. 418 - 426 (2021/02/01)
Switchable imine and amine synthesis catalyzed by a tripodal ligand-supported well-defined cobalt complex is presented herein. A large variety of primary alcohols and amines were selectively converted to imines or amines in good to excellent yields. It is discovered that the base plays a crucial role on the selectivity. A catalytic amount of base leads to the imine formation, while an excess loading of base results in the amine product. This strategy on product selectivity also strongly depends on the organometallic catalysts in use. We expect that the present study could provide useful insights toward selective organic synthesis and catalyst design.
Copper-Catalyzed Intramolecular Amination of C(sp3)-H Bond of Secondary Amines to Access Azacycles
Jin, Ruo-Xing,Dai, Jing-Cheng,Li, Yan,Wang, Xi-Sheng
supporting information, p. 421 - 426 (2021/01/26)
The cross-coupling of C-N bond directly from inert C-H bonds is an ideal approach to synthesize saturated azacycles due to its high efficiency and atom economy. In this article, a copper-catalyzed intramolecular amination via the cross coupling of C(sp3)-H and N-H bonds of secondary amine has been reported, which exhibit excellent chemo- and regioselectivity, extensive substrate scope, and functional group tolerance in good to excellent yield, offering an efficient pathway to build nitrogen-containing heterocycle skeletons.
Metal-free regioselective C-H amination for the synthesis of pyrazole-containing 2H-indazoles
Wang, Kai,Wei, Tingting,Zhang, Yujia,Hou, Jiahao,Bai, Renren,Xie, Yuanyuan
, p. 1787 - 1794 (2021/03/14)
A general and practical regioselective approach for the C-H amination of 2H-indazoles under transition-metal-free conditions was developed. A series of substrates were tested showing eminent functional group tolerance and affording the C-N functionalization products in good to excellent yields. Mechanism studies revealed that a radical process was involved in this transformation.
Sulfated polyborate: A dual catalyst for the reductive amination of aldehydes and ketones by NaBH4
Ganwir, Prerna,Chaturbhuj, Ganesh
supporting information, (2021/05/19)
An efficient, quick, and environment-friendly one-pot reductive amination of aldehydes or ketones was developed. In ethanol at 70 °C, a imination catalyzed by sulfated polyborate and further reduced by sodium borohydride yields various amines. The present method has many significant benefits, including a shorter reaction time, excellent yields, and a hassle-free, straightforward experimental process. The reaction has a wide range of applications due to its flexibility, including secondary amine for reductive amination.
Rhodium catalyzed multicomponent dehydrogenative annulation: one-step construction of isoindole derivatives
Cheng, Biao,Lyu, Hairong,Quan, Yangjian,Xie, Zuowei
supporting information, p. 7930 - 7933 (2021/08/17)
A strategy for one-pot synthesis of isoindoles is describedviaa catalytic multicomponent dehydrogenative annulation of diarylimines, vinyl ketones and simple amines. In the presence of a rhodium catalyst and Cu oxidant, four C-H and two N-H bonds are activated along with the formation of one new C-C and two new C-N bonds, leading to a series of isoindole derivatives in good to very high isolated yields.
Rhodium-Catalyzed Dehydrogenative Annulation of N-Arylmethanimines with Vinylene Carbonate for Synthesizing Quinolines
Hu, Yan,Nan, Jiang,Yin, Jiacheng,Huang, Guanjie,Ren, Xin,Ma, Yangmin
supporting information, p. 8527 - 8532 (2021/11/13)
Here we report a novel Rh-catalyzed C-H/C-H alkenylation of N-arylmethanimines with vinylene carbonate acting as a vinylene unit. Forty examples of C3,C4-nonsubstituted quinolines were achieved from commercially available starting materials. This identified process features an exceedingly simple system, a lower loading of catalyst, and the capacity for postfunctionalization with bioactive molecules.
Cooperative catalysis of molybdenum with organocatalysts for distribution of products between amines and imines
Wu, Di,Bu, Qingqing,Guo, Cheng,Dai, Bin,Liu, Ning
, (2021/02/02)
Multi-amino groups and nitrogen donors compound was discovered as an organocatalyst for N-alkylation of alcohols with amines in the presence of Mo(CO)6. The Mo(CO)6/organocatalyst binary system has shown to be a highly active catalyst for the N-alkylation reaction between alcohols and amines with excellent tolerance of variable starting materials bearing different functional groups. Of particular note, this method possessing a superiority selectivity in the synthesis of N-alkylated amines or imines, which can be controlled by the reaction temperature. The cooperative catalysis mechanism in combination of Mo(CO)6 with organocatalyst was elucidated by control experiments.
