23947-37-7Relevant academic research and scientific papers
Ru-NHC-Catalyzed Asymmetric Hydrogenation of 2-Quinolones to Chiral 3,4-Dihydro-2-Quinolones
Daniliuc, Constantin,Glorius, Frank,Hu, Tianjiao,Lückemeier, Lukas
supporting information, p. 23193 - 23196 (2021/09/25)
Direct enantioselective hydrogenation of unsaturated compounds to generate chiral three-dimensional motifs is one of the most straightforward and important approaches in synthetic chemistry. We realized the Ru(II)-NHC-catalyzed asymmetric hydrogenation of 2-quinolones under mild reaction conditions. Alkyl-, aryl- and halogen-substituted optically active dihydro-2-quinolones were obtained in high yields with moderate to excellent enantioselectivities. The reaction provides an efficient and atom-economic pathway to construct simple chiral 3,4-dihydro-2-quinolones. The desired products could be further reduced to tetrahydroquinolines and octahydroquinolones.
HFIP-mediated strategy towards β-oxo amides and subsequent Friedel-Craft type cyclization to 2?quinolinones using recyclable catalyst
Kabi, Arup K.,Gujjarappa, Raghuram,Vodnala, Nagaraju,Kaldhi, Dhananjaya,Tyagi, Ujjawal,Mukherjee, Kalisadhan,Malakar, Chandi C.
supporting information, (2020/10/20)
A simple and cost-effective 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)-mediated protocol for the synthesis of β-oxo amides has been described by using amines and β-keto esters as substrates. The reaction conditions were found to be highly efficient towards the cleavage of C[sbnd]O bond and consequent formation of the products in excellent yields and selectivity. The obtained β-oxo amides were further transformed in to the synthetically useful 2?quinolinones via intramolecular Friedel-Craft type cyclization of aromatic ring using ferrites as a recyclable catalyst. A spectrum of substrates bearing broad range of functional groups were well tolerated under the reaction conditions. The proposed mechanistic pathways were substantially verified by literature and mass-spectroscopic evidences.
Lactamization of alkenyl C-H bonds to generate 2-quinolinones with triphosgene
Du, Guizhi,Wang, Zixiao,Zhang, Zhen
, p. 600 - 608 (2020/06/03)
A simple and easy-going method is developed to synthesize the analogues of 2-quinolinones by using triphosgene (BTC) as the carbonyl source. In these reactions, both the toxic carbon monoxide (CO) and phosgene are avoided and the 2-quinolinones are obtained in moderate to good yields under mild conditions, all of which are anticipated to be meaningful in both industry and laboratory.
Synthesis and antileishmanial evaluation of thiazole orange analogs
Abdelhameed, Ahmed,Liao, Xiaoping,McElroy, Craig A.,Joice, April C.,Rakotondraibe, Liva,Li, Junan,Slebodnick, Carla,Guo, Pu,Wilson, W. David,Werbovetz, Karl A.
supporting information, (2019/11/28)
Cyanine compounds have previously shown excellent in vitro and promising in vivo antileishmanial efficacy, but the potential toxicity of these agents is a concern. A series of 22 analogs of thiazole orange ((Z)-1-methyl-4-((3-methylbenzo[d]thiazol-2(3H)-ylidene)methyl)quinolin-1-ium salt), a commercial cyanine dye with antileishmanial activity, were synthesized in an effort to increase the selectivity of such compounds while maintaining efficacy. Cyanines possessing substitutions on the quinolinium ring system displayed potency against Leishmania donovani axenic amastigotes that differed little from the parent compound (IC50 12–42 nM), while ring disjunction analogs were both less potent and less toxic. Changes in DNA melting temperature were modest when synthetic oligonucleotides were incubated with selected analogs (ΔTm ≤ 5 °C), with ring disjunction analogs showing the least effect on this parameter. Despite the high antileishmanial potency of the target compounds, their toxicity and relatively flat SAR suggests that further information regarding the target(s) of these molecules is needed to aid their development as antileishmanials.
Compounds having anticonvulsion activity, preparing methods thereof and applications of the compounds
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Paragraph 0051; 0052, (2017/10/05)
The invention provides 7-substituted-5-methyl-1,2,4-triazolo[4,3-a] quinoline and 7-substituted-5-ethoxy-[1,2,4]-triazolo[4,3-a] quinoline compounds having anticonvulsion activity, preparing methods thereof and applications of the compounds in the field of preparing anticonvulsion medicines.
Lactamization of sp2C?H Bonds with CO2: Transition-Metal-Free and Redox-Neutral
Zhang, Zhen,Liao, Li-Li,Yan, Si-Shun,Wang, Lei,He, Yun-Qi,Ye, Jian-Heng,Li, Jing,Zhi, Yong-Gang,Yu, Da-Gang
supporting information, p. 7068 - 7072 (2016/07/06)
The first direct use of carbon dioxide in the lactamization of alkenyl and heteroaryl C?H bonds to synthesize important 2-quinolinones and polyheterocycles in moderate to excellent yields is reported. Carbon dioxide, a nontoxic, inexpensive, and readily available greenhouse gas, acts as an ideal carbonyl source. Importantly, this transition-metal-free and redox-neutral process is eco-friendly and desirable for the pharmaceutical industry. Moreover, these reactions feature a broad substrate scope, good functional group tolerance, facile scalability, and easy product derivatization.
Ruthenium-catalyzed cyclization of anilides with substituted propiolates or acrylates: An efficient route to 2-quinolinones
Manikandan, Rajendran,Jeganmohan, Masilamani
supporting information, p. 3568 - 3571 (2014/07/21)
A Ru-catalyzed cyclization of anilides with propiolates or acrylates affording 2-quinolinones having diverse functional groups in good to excellent yields is described. Later, 2-quinolinones were converted into 3-halo-2-quinolinones and 2-chloroquinolines
An environmentally benign one pot synthesis of substituted quinolines catalysed by fluoroboric acid based ionic liquid
Rajendran, A.,Karthikeyan, C.,Rajathi, K.,Ragupathy, D.
, p. 877 - 881,5 (2020/09/09)
Organic synthesis generally required large amount of solvent, avoiding the use of organic solvents in synthesis is a paradigm shift directed at developing more benign chemistry, and with ionic liquids surprisingly can lead to access to new compounds. An elegant one-pot synthesis of quinoline derivatives has been achieved by reaction of substituted anilines with β-ketoester at 60°C in ethanol using an ionic liquid [Et3NH]+[BF 4]- as catalyst. All the reactions gave products with high degree of purity and excellent yield (78.93%) within the shorter span of time (20.65 min) than those reactions with conventional methods. The screening of solvents as well as the reuse of ionic liquid has been evaluated. The structure of the products has been elucidated by spectral and analytical data. The present scope and potential economic impact of the reaction are demonstrated by the synthesis of substituted quinolines. Remaining challenges and future perspectives of the new transformation are discussed.
Diastereoselective hydrogenation of substituted quinolines to enantiomerically pure decahydroquinolines
Heitbaum, Maja,Froehlich, Roland,Glorius, Frank
supporting information; experimental part, p. 357 - 362 (2010/05/19)
The stereoselective hydrogenation of auxiliary-substituted quinolines was used to build up saturated and partially saturated heterocycles. In a first step, the formation and diastereoselective hydrogenation of 2-oxazolidinone- substituted quinolines to 5,6,7,8-tetrahydroquinolines is reported. In this unprecedented process, stereocenters on the carbocyclic quinoline ring were formed with a dr of up to 89:11. Platinum oxide as a catalyst and trifluoroacetic acid as a solvent were found to be optimal for high levels of chemo- and stereoselectivity in this step. In a second hydrogenation step, the completely saturated decahydroquinolines with 4 newly formed stereocenters were obtained with enantioselectivities of up to 99%. Rhodium on carbon as a catalyst and acetic acid as a solvent gave the best results for this hydrogenation and allowed a traceless cleavage of the chiral auxiliary. Thus, this new method allows an efficient stereoselective synthesis of valuable 5,6,7,8-tetrahydro- and decahydroquinoline products.
An environmentally benign indium (III) chloride catalysed one-pot synthesis of quinolines
Kidwai, Mazaahir,Bansal, Vikas,Mishra, Neeraj Kumar,Bhatnagar, Divya
experimental part, p. 746 - 748 (2009/12/28)
A convenient eco-friendly procedure for the quantitative synthesis of novel quinoline derivatives has been developed by a simple one-pot reaction of substituted anilines with P-ketoesters at 60°C in ethanol using recyclable indium chloride as catalyst. The reaction proceeds smoothly under solvent free conditions with quantitative yields.
