1721-92-2Relevant academic research and scientific papers
Reactions of azides with electrophiles: New methods for the generation of cationic 2-azabutadienes. Synthesis of 1,2,3,4-tetrahydroquinolines and 1,2-dihydroquinolines via a hetero Diels-Alder reaction
Pearson, William H.,Fang, Wen-Kui
, p. 39 - 46 (1997)
Two methods for the generation of iminium ions of the type ArN+(X)=CHR (X = H or alkyl, R = H or alkyl) are reported: (1) the Bronsted-acid-promoted rearrangement of benzylic azides and (2) the intermolecular Schmidt reactions of azides XN3 (X = aliphatic) with benzylic carbocations derived from benzylic alcohols ArCH(R)OH. The iminium ions ArN+(X)=CHR behave as cationic 2-azabutadienes in the presence of alkenes and alkynes, producing 1,2,3,4-tetrahydroquinolines and 1,2-dihydroquinolines by a hetero Diels-Alder reaction.
Synthesis of quinolines: Via sequential addition and I2-mediated desulfurative cyclization
Gao, Ziwei,Jian, Yajun,Sun, Huaming,Wang, Yanyan,Yang, Mingming,Zhang, Guofang,Zhang, Weiqiang
supporting information, p. 38889 - 38893 (2021/12/20)
An efficient one-pot approach for the synthesis of quinolines from o-aminothiophenol and 1,3-ynone under mild conditions is disclosed. With the aid of ESI-MS analysis and parallel experiments, a three-step mechanism is proposed - a two-step Michael additi
Carbocatalytic Cascade Synthesis of Polysubstituted Quinolines from Aldehydes and 2-Vinyl Anilines
Bulatov, Evgeny,Helaja, Juho,Hu, Tao,Lenarda, Anna,M?kel?, Mikko K.,Malinen, Kiia,Melchionna, Michele,Nieger, Martin,Talvitie, Juulia,Wirtanen, Tom
supporting information, p. 3775 - 3782 (2021/07/20)
Oxidized active carbon (oAC) catalyses the formation of polysubstituted quinolines from o-vinyl anilines and aldehydes. The reaction proceeds in a cascade manner through condensation, electrocyclization and dehydrogenation, and gives access to a wide range of quinolines with alkyl and/or aryl substituents as demonstrated with 40 examples. The metal-free catalytic procedure allows a heterogeneous protocol for the synthesis of various polysubstituted quinolines. The mechanistic studies imply that both the acid and quinoidic groups in oAC are integral for the catalytic manifold. (Figure presented.).
PEG-400 as a carbon synthon: Highly selective synthesis of quinolines and methylquinolines under metal-free conditions
Ding, Chengcheng,Feng, Kaili,Li, Shichen,Ma, Chen
, p. 5542 - 5548 (2021/08/16)
A metal-free, peroxide-free, and efficient procedure for the highly selective synthesis of quinolines and methylquinolines was reported. The main feature of this method was that the same substrate can produce quinolines and methylquinolines, respectively, under different reaction conditions. PEG-400 was used as both a reactant and solvent in this reaction. The utility of the designed procedure was also demonstrated by the derivatization of the products to bioactive compounds. This journal is
Visible-light-mediated organoboron-catalysed metal-free dehydrogenation of N-heterocycles using molecular oxygen
Wei, Lanfeng,Wei, Yu,Xu, Liang,Zhang, Jinli
supporting information, p. 4446 - 4450 (2021/06/30)
The surge of photocatalytic transformation not only provides unprecedented synthetic methods, but also triggers the enthusiasm for more sustainable photocatalysts. On the other hand, oxygen is an ideal oxidant in terms of atom economy and environmental friendliness. However, the poor reactivity of oxygen at the ground state makes its utilization challenging. Herein, a visible-light-induced oxidative dehydrogenative process is disclosed, which uses an organoboron compound as the photocatalyst and molecular oxygen as the sole oxidant.Viathis approach, an array of N-heterocycles have been accessed under metal-free mild conditions, in good to excellent yields.
Environmentally Friendly Nafion-Mediated Friedl?nder Quinoline Synthesis under Microwave Irradiation: Application to One-Pot Synthesis of Substituted Quinolinyl Chalcones
Chan, Chieh-Kai,Lai, Chien-Yu,Wang, Cheng-Chung
, p. 1779 - 1794 (2020/06/08)
An efficient and eco-friendly synthetic route for Friedl?nder quinoline synthesis of polysubstituted quinolines is described. This green chemical method starts from various 2-aminobenzophenones and mono- or dicarbonyl synthons and uses reusable Nafion NR50 material as a solid catalyst in ethanol under microwave irradiation. The protocol has a high generality of functional groups and provides the desired quinolines in good to excellent yields. Some structures were confirmed by single-crystal X-ray diffraction analysis.
ZnMe2-Mediated, Direct Alkylation of Electron-Deficient N-Heteroarenes with 1,1-Diborylalkanes: Scope and Mechanism
Jo, Woohyun,Baek, Seung-Yeol,Hwang, Chiwon,Heo, Joon,Baik, Mu-Hyun,Cho, Seung Hwan
supporting information, p. 13235 - 13245 (2020/09/01)
The regioselective, direct alkylation of electron-deficient N-heteroarenes is, in principle, a powerful and efficient way of accessing alkylated N-heteroarenes that are important core structures of many biologically active compounds and pharmaceutical agents. Herein, we report a ZnMe2-promoted, direct C2- or C4-selective primary and secondary alkylation of pyridines and quinolines using 1,1-diborylalkanes as alkylation sources. While substituted pyridines and quinolines exclusively afford C2-alkylated products, simple pyridine delivers C4-alkylated pyridine with excellent regioselectivity. The reaction scope is remarkably broad, and a range of C2- or C4-alkylated electron-deficient N-heteroarenes are obtained in good yields. Experimental and computational mechanistic studies imply that ZnMe2 serves not only as an activator of 1,1-diborylalkanes to generate (α-borylalkyl)methylalkoxy zincate, which acts as a Lewis acid to bind to the nitrogen atom of the heterocycles and controls the regioselectivity, but also as an oxidant for rearomatizing the dihydro-N-heteroarene intermediates to release the product.
Metal-Free Synthesis of 2-Substituted Quinolines via High Chemoselective Domino Condensation/Aza-Prins Cyclization/Retro-Aldol between 2-Alkenylanilines with β-Ketoesters
Nan, Jiang,Chen, Pu,Zhang, Yuxin,Yin, Yun,Wang, Bo,Ma, Yangmin
, p. 14042 - 14054 (2020/11/13)
A highly chemoselective domino condensation/aza-Prins cyclization/retro-aldol between 2-alkenylanilines with β-dicarbonyl compounds under metal-free conditions was accomplished, giving a large category of valuable 2-substituted quinolines in good yields with excellent functional group toleration. This newly established process, adopting β-ketoesters as masked C1 synthons via C-C cleavage, could even be simplified into a three-component [3 + 2 + 1] domino version consisting of exceedingly low-priced commercial starting materials. The synthetic application of products was exemplified by several intriguing chemical operations.
A Heck reaction/photochemical alkene isomerization sequence to prepare functionalized quinolines
Donohoe, Timothy J.,Hoff, Oskar,Hoffman, Jack B.,Kelly, Alex,Walker, Johannes C. L.,Werrel, Simon
, (2020/08/06)
A route to prepare functionalized quinolines based on a Heck reaction/UV-induced alkene isomerization sequence is described. The method allows for the preparation of quinolines under mild and neutral conditions and has broad functional group tolerance. Acid-sensitive functional groups that would not be tolerated under previous approaches can be included and a one-pot quinoline forming procedure is also reported.
Quinoline compound and synthesis method thereof
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Paragraph 0161-0165, (2020/02/14)
The invention discloses a synthesis method of a quinoline compound. The synthesis method comprises the following steps: adding a diazocarbonyl compound and a 2-vinylaniline compound into a solvent, carrying out a reaction under the protection of an inert
