1076-28-4Relevant academic research and scientific papers
Development of one-pot benzylic amination reactions of azine N-oxides
Liman, Menek?e,Türkmen, Yunus Emre
, p. 1723 - 1727 (2018)
An efficient one-pot synthetic methodology has been developed for the benzylic amination reactions of methyl-substituted azine N-oxides that operate under mild conditions. The reaction was found to tolerate quinoline and isoquinoline N-oxides with electron donating and withdrawing substituents as the electrophilic reaction partners as well as a broad range of nucleophilic primary, secondary and aromatic amines, affording the benzylic amination products in up to 82% yield.
Rh(III)-Catalyzed C(8)-H Functionalization of Quinolines via Simultaneous C-C and C-O Bond Formation: Direct Synthesis of Quinoline Derivatives with Antiplasmodial Potential
Sharma, Ritika,Kumar, Rakesh,Kumar, Rohit,Upadhyay, Pooja,Sahal, Dinkar,Sharma, Upendra
, p. 12702 - 12710 (2018)
Here, a facile and efficient protocol for the synthesis of 3-hydroxyquinolin-8-yl propanoates via Rh(III)-catalyzed C(8)-H activation of 2-substituted quinolines has been developed. The reaction proceeds via C(8)-H activation, functionalization with acrylates, followed by intramolecular migration of the oxygen atom from quinoline N-oxides to the acrylate moiety. In this approach, N-oxide plays a dual role of a traceless directing group as well as a source of an oxygen atom for hydroxylation. This catalytic method involves simultaneous formation of new C-C and C-O bonds and is applicable only for C2-substituted quinolines. A catalytically competent five-membered rhodacycle has been characterized, thus revealing a key intermediate in the catalytic cycle. In silico docking studies against Falcipan-2 have revealed that 3a, 3b, 3g, and 3m have better scores. In vitro evaluation of selected compounds against CQ-sensitive pf3D7 and CQ-resistant pfINDO strains provided evidence that 3d (IC50 13.3 μM) and 3g (IC50 9.5 μM) had good promise against Plasmodium falciparum in the in vitro culture. Compound 3g was found to be the most potent on the basis of both in vitro antiplasmodial activity [IC50 9.5 μM (Pf3D7) and 11.9 μM (PfINDO), resistance index 1.25] and in silico studies.
An unusual de-nitro reduction of 2-substituted-4-nitroquinolines
Zhou, Yu,Li, Jian,Liu, Hong,Zhao, Linxiang,Jiang, Hualiang
, p. 8511 - 8514 (2006)
The treatment of a variety of 2-substituted-4-nitroquinolines with Sn in the presence of concentrated hydrochloric acid in ethanol at 70 °C for 2-4 h afforded unusual de-nitro products 2-substituted-quinolines in good yields.
A simple, regioselective synthesis of 1,4-bis(tert-butoxycarbonylmethyl)-tetraazacyclododecane
Li, Cong,Wong, Wing-Tak
, p. 2956 - 2959 (2003)
A convenient synthetic route to 1,4-bis(tert-butoxycarbonylmethyl)tetraazacyclododecane (cyclen) (1) with high yield and excellent regioselectivity is described. Compound 1 reacted with a range of functionalized alkyl halides under two reaction conditions to give mono-N-alkylated 1,4-bis(tert-butoxycarbonylmethyl)tetraazacyclododecane (2-9) in good yield.
Baker's yeast reduction of nitroarenes in NaOH media 5. Reductive cyclization of o-nitrocinnamaldehydes
Baik, Woonphil,Kim, Dong Ik,Lee, Hyun Joo,Chung, Wook-Jin,Kim, Byeong Hyo,Lee, Seok Woo
, p. 4579 - 4580 (1997)
Reduction of 2-nitrocinnamaldehydes or 4-(2'-nitrophenyl)-3-buten-2-one by bakers' yeast has been found to be cyclized in NaOH media, resulting in the formation of quinolines via cyclized N-oxides.
Rhodium-Catalyzed Remote C-8 Alkylation of Quinolines with Activated and Unactivated Olefins: Mechanistic Study and Total Synthesis of EP4 Agonist
Sharma, Ritika,Kumar, Inder,Kumar, Rakesh,Sharma, Upendra
, p. 3022 - 3028 (2017)
Reported herein is a rhodium(III)-catalyzed regioselective distal C(sp2)-H bond alkylation of quinoline N-oxides using olefins as alkyl source and N-oxide as the traceless directing group. The reaction exhibits broad substrate scope with excellent selectivity for C-8 position and good yields of alkylated products. The usefulness of the developed catalytic protocol is established by synthesis of EP4 agonist. In mechanistic study, C-8 olefinated quinoline was identified as the reaction intermediate, which gets reduced to desired C-8 alkylated product in the presence of a rhodium(I) species (produced from rhodium(III) during reaction) and formic acid. Formic acid is produced from dimethylformamide in the presence of silver tetrafluoroborate. (Figure presented.).
Rh/O2-Catalyzed C8 Olefination of Quinoline N-Oxides with Activated and Unactivated Olefins
Sharma, Ritika,Kumar, Rakesh,Sharma, Upendra
, p. 2786 - 2797 (2019)
The rhodium/O2 system-catalyzed distal C(sp2)-H olefination of quinoline N-oxides is developed. Molecular oxygen has been explored as an economic and clean oxidant, an alternative to inorganic oxidants. A wide substrate scope with respect to quinoline N-oxides and olefins (activated acrylates and styrenes; unactivated aliphatic olefins) demonstrates the robustness of the developed catalytic method. Interestingly, 2-substituted quinoline N-oxides also afforded good yields of the corresponding C8-olefinated products. Kinetic isotope studies and deuterium-labeling experiments have been performed to understand the preliminary mechanistic pathway. The applicability of the developed method is demonstrated by utilizing natural product-derived substrates and by converting the C8-olefinated quinoline N-oxides into various other useful molecules.
RhIII-Catalyzed Direct C8-Arylation of Quinoline N-Oxides using Diazonaphthalen-2(1H)-ones: A Practical Approach towards 8-aza BINOL
Ghosh, Bidhan,Biswas, Aniruddha,Chakraborty, Soumen,Samanta, Rajarshi
, p. 2388 - 2392 (2018)
An efficient RhIII-catalyzed redox-neutral method for the direct C8-arylation of quinoline N-oxides using diazonaphthalen-2(1H)-one as coupling partner has been demonstrated. The developed method is simple, scalable and straightforward with a w
Nickel(0)-catalyzed couplings of vinyl- alanes and -zirconocenes with chloromethylated heteroaromatics: A route to E-allylated heterocycles
Lipshutz, Bruce H.,Kim, Sung-Kyu,Mollard, Paul,Blomgren, Peter A.,Stevens, Kirk L.
, p. 6999 - 7012 (1998)
Treatment of selected chloromethylated heteroaromatics, including pyridines, thiophenes, and furans, with vinyl alanes or vinyl zirconocenes in the presence of Ni(O) results in E-allylated products in good yields.
N2H4-H2O Enabled Umpolung Cyclization of o-Nitro Chalcones for the Construction of Quinoline N-Oxides
Zhang, Guan,Yang, Kai,Wang, Shihui,Feng, Qiang,Song, Qiuling
supporting information, p. 595 - 600 (2021/02/03)
Umpolung is a unique strategy which converts the property of an atom into the opposite one. An efficient and general method for the construction of quinoline N-oxides via umpolung of carbonyl groups was developed from ortho-nitro chalcones and hydrazine i
