65023-69-0Relevant academic research and scientific papers
Ce(IV) immobilized on halloysite nanotube–functionalized dendrimer (Ce(IV)–G2): A novel and efficient dendritic catalyst for the synthesis of pyrido[3,2-c]coumarin derivatives
Ataee-Kachouei, Tahereh,Nasr-Esfahani, Mahboobeh,Mohammadpoor-Baltork, Iraj,Mirkhani, Valiollah,Moghadam, Majid,Tangestaninejad, Shahram,Notash, Behrouz
, (2020)
In this study, a new and stable Ce(IV) immobilized on halloysite nanotube–functionalized dendrimer was designed, synthesized, and characterized using Fourier-transform infrared, elemental analysis, thermogravimetric analysis, field emission scanning electron microscopy, scanning electron microscopy–energy dispersive X-ray spectroscopy, transmission electron microscopy, dynamic light scattering, Brunauer–Emmett–Teller, and inductively coupled plasma optical emission spectroscopy techniques. This catalyst was efficiently used for the one-pot, single-step multicomponent synthesis of pyrido[3,2-c]coumarins from 4-aminocoumarin, aldehydes, and aryl ketones. The efficiency and selectivity of this catalytic system were also evaluated for the synthesis of pyrido[3,2-c]coumarins from terminal/internal alkynes instead of aryl ketones. In this respect, the regioselectivity of the products was successfully assigned by X-ray crystallographic analysis. All these reactions were best performed under solvent-free conditions in the presence of only 0.28 mol% of the catalyst, and such a one-pot multicomponent synthesis of pyrido[3,2-c]coumarins is reported for the first time. It is also worth noting that single-step and short reaction path for the synthesis of a variety of pyrido[3,2-c]coumarins along with excellent reusability of this dendritic catalyst makes this method economically and environmentally attractive.
Synthetic method for 2,4-diphenylpyrido[3,2-c]coumarin
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Paragraph 0018-0029, (2020/01/03)
The invention discloses a synthetic method for 2,4-diphenylpyrido[3,2-c]coumarin. The method is specifically performed according to the following steps: performing a reaction at room temperature for 4h by using 4-aminocoumarin represented by a formula I s
2,3-Dichloro-5,6-Dicyano-1,4-Benzoquinone (DDQ)-Mediated Tandem Oxidative Coupling/Intramolecular Annulation/Dehydro-Aromatization for the Synthesis of Polysubstituted and Fused Pyridines
Cheng, Dongping,Deng, Zhiteng,Yan, Xianhang,Wang, Mingliang,Xu, Xiaoliang,Yan, Jizhong
, p. 5025 - 5029 (2019/11/03)
A DDQ-mediated tandem reaction of 1,3-diarylpropenes and β-enaminoesters/4-aminocoumarins is disclosed. It involves oxidative coupling, intramolecular annulation and dehydro-aromatization reaction, which provides an efficient and mild method for the synthesis of polysubstituted and fused pyridines under metal-free conditions. (Figure presented.).
Copper Catalysis for Nicotinate Synthesis through β-Alkenylation/Cyclization of Saturated Ketones with β-Enamino Esters
Ling, Fei,Xiao, Lian,Fang, Lu,Lv, Yaping,Zhong, Weihui
supporting information, p. 444 - 448 (2017/12/04)
The first example of a Cu-catalyzed and 4-OH-TEMPO mediated intermolecular [3+3] annulation of saturated ketones with β-enamino esters is reported herein, which was successfully used for the synthesis of versatile nicotinates through sequential β-C(sp3)-H bond alkenylation, enamine-carbonyl condensation and aromatization. This protocol tolerates a variety of functional groups, thereby providing a practical and efficient method for the fabrication of 5H-chromeno[4,3-b]pyridin-5-one skeletons. (Figure presented.).
