197729-98-9Relevant academic research and scientific papers
Transformation of fluorinated 2-alkynylanilines by various catalytic systems
Politanskaya, Larisa,Petyuk, Maxim,Tretyakov, Evgeny
, (2019/11/11)
Simple and efficient approaches to the synthesis of fluorinated benzoazaheterocycles with good yields are reported. Firstly a series of polyfluorinated 2-alkynylanilines – the versatile building blocks – was synthesized by the Sonogashira reaction of o-iodoaniline with terminal alkynes. Then the transformations of the obtained 2,3,4-trifluo-6-alkynilanilines in the presence of KOH or PdCl2 in MeCN, and in the presence of monohydrate of p-toluenesulfonic acid (p-TSA?H2O) in MeOH, EtOH or benzene were investigated. It was found that Ph- and n-Bu-containing alkynylanilines by action of PdCl2 in MeCN underwent an intramolecular cyclization reaction to produce the corresponding indoles in high yields. The reaction of KOH with alkynes containing the tertiary alcohol function at the triple bond produced the unsubstituted on the pyrrole ring indole. It was found that fluorinated 2-alkynilanilines can be transformated into indoles, 2-arylketones and 2,3-dihydroquinolines by action of p-TSA?H2O in boiling alcohols, depending on the substituent at the triple bond. The use of benzene as a solvent in the reaction of p-TSA?H2O with polyfluorinated alkynes, bearing an alcohol group resulted in representative series of 2,3-dihydroquinolinones containing a substituents R1 and R2 in the 2nd position of their structure (R = H, H; Me, Me; H, i-Pr; H, Ph).
An Improved Environmentally Friendly Approach to 4-Nitro-, 4-Sulfonyl-, and 4-Aminoquinolines and 4-Quinolones through Conjugate Addition of Nucleophiles to β-(2-Aminophenyl)-α,β-ynones
Rode, Navnath D.,Arcadi, Antonio,Chiarini, Marco,Marinelli, Fabio
, p. 2501 - 2512 (2017/05/22)
Sequential addition/annulation reactions of sulfinate and nitrite anions to β-(2-aminophenyl)-α,β-ynones led to valuable 4-sulfonylquinolines and 4-nitroquinolines. The latter proved to be versatile precursors of N-unsubstituted 4-aminoquinolines and 4-quinolones. Reaction of β-(2-aminophenyl)-α,β-ynones with DMF/NaOH resulted in the formation of 4-(dimethylamino)quinolines. The use of an alternative CO-free procedure for the preparation of substrates β-(2-aminophenyl)-α,β-ynones allowed extension of the methodology to the synthesis of 4-substituted 2-alkylquinolines.
Au-catalyzed formation of functionalized quinolines from 2-alkynyl arylazide derivatives
Gronnier, Colombe,Boissonnat, Guillaume,Gagosz, Fabien
, p. 4234 - 4237 (2013/09/12)
A new method for converting 2-alkynyl arylazide derivatives into functionalized polysubstituted quinolines following a gold-catalyzed 1,3-acetoxy shift/cyclization/1,2-group shift sequence has been developed. This transformation proceeds under mild reaction conditions, is efficient, and tolerates a large variety of functional groups.
Efficient preparation of 4-hydroxyquinolin-2(1 H)-one derivatives with silver-catalyzed carbon dioxide incorporation and intramolecular rearrangement
Ishida, Tomonobu,Kikuchi, Satoshi,Yamada, Tohru
supporting information, p. 3710 - 3713 (2013/08/23)
Although 4-hydroxyquinolin-2(1H)-one derivatives have attracted much attention due to their biological benefits, conventional reactions under harsh heat conditions must be employed to provide these key compounds. In the presence of a catalytic amount of s
Palladium-catalyzed intermolecular aerobic oxidative cyclization of 2-ethynylanilines with isocyanides: Regioselective synthesis of 4-halo-2-aminoquinolines
Liu, Bifu,Gao, Hanling,Yu, Yue,Wu, Wanqing,Jiang, Huanfeng
supporting information, p. 10319 - 10328 (2013/11/06)
A robust and regioselective palladium-catalyzed intermolecular aerobic oxidative cyclization of 2-ethynylanilines with isocyanides to the synthesis of 4-halo-2-aminoquinolines is reported herein. The procedure constructs various 4-halo-2-aminoquinolines w
2-Substituted-2,3-dihydro-1 H -quinolin-4-ones via acid-catalyzed tandem rupe rearrangement-donnelly-farrell ring closure of 2-(3′-hydroxypropynyl) anilines
Pisaneschi, Federica,Sejberg, Jimmy J. P.,Blain, Cecile,Ng, Wang Hei,Aboagye, Eric O.,Spivey, Alan C.
, p. 241 - 244 (2011/04/16)
A range of 2-substituted 2,3-dihydro-1H-quinolin-4-ones have been synthesized from anilines by a two-step process involving Sonogashira coupling with a propargyl alcohol then acid-catalyzed cyclization of the resulting 2-(3′-hydroxypropynyl)anilines. The cyclization reaction appears to proceed via regioselective rearrangement of the propargyl alcohol to an α,β-unsaturated ketone (Rupe rearrangement) and then 6-endo-trig ring closure (Donnelly-Farrell cyclization). The isolation of the α,β-unsaturated ketone intermediate in one example supports this pathway. Georg Thieme Verlag Stuttgart.
3-(o-Trifluoroacetamidoaryl)-1-propargylic esters: common intermediates for the palladium-catalyzed synthesis of 2-aminomethyl-, 2-vinylic, and 2-alkylindoles
Ambrogio, Ilaria,Cacchi, Sandro,Fabrizi, Giancarlo,Prastaro, Alessandro
experimental part, p. 8916 - 8929 (2009/12/07)
3-(o-Trifluoroacetamidoaryl)-1-propargylic esters have been used as common synthetic intermediates for the preparation of a variety of 3-unsubstituted 2-substituted indoles. Treating ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates unsubstituted or containing an aryl substituent at the propargylic carbon with piperazines and Pd(PPh3)4 in THF at 80 °C affords 2-(piperazin-1-ylmethyl)indoles in excellent yields. Good to excellent yields of 2-aminomethylindoles are also obtained with other secondary amines. Ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates bearing an alkyl substituent at the propargylic carbon and ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic acetates disubstituted at the propargylic carbon give 2-vinylic indoles with the Pd(OAc)2/PPh3 combination and Et3N in THF at 80 °C. Formation of 2-vinylic indoles is quite stereoselective, generating trans vinylic derivatives, at least with the substrates that we have investigated. In the presence of formic acid, Et3N, and Pd(PPh3)4 in MeCN at 80 °C, ethyl 3-(o-trifluoroacetamidoaryl)-1-propargylic carbonates afford 2-alkylindoles in good to excellent yields.
Palladium-catalyzed Sonogashira coupling reaction followed by isomerization and cyclization
Cho, Chan Sik
, p. 4094 - 4097 (2007/10/03)
2-Iodoaniline reacts with terminal acetylenic carbinols in THF at 80 °C in the presence of a catalytic amount of PdCl2(PPh3) 2 and CuI along with aqueous tetrabutylammonium hydroxide to afford the corresponding 2-arylquinolines in good yields. The catalytic pathway seems to be proceeded via a sequence involving initial Sonogashira coupling between 2-iodoaniline and terminal acetylenic carbinols to form coupled acetylenic carbinols, isomerization of coupled acetylenic carbinols to α,β- unsaturated ketones, and cyclodehydration.
Palladium-catalyzed heteroannulation with acetylenic carbinols as synthons-synthesis of quinolines and 2,3-dihydro-4(1H)-quinolones
Mahanty, Jyan S.,De, Mahuya,Das, Palas,Kundu, Nitya G.
, p. 13397 - 13418 (2007/10/03)
o-Iodoanilides 4 reacted with terminal acetylenic carbinols 5 under palladium-catalyzed conditions to yield o-substituted anilides 6. Most of the anilides 6 could be cyclized with NaOEt/EtOH to 2-arylquinolines 2. o-Iodoanilines 7 reacted with carbinols 5 leading to 8 which on palladium(II) assisted cyclisation afforded substituted quinolines 2. An excellent synthesis of the alkaloid dubamine (2n) is reported. Also, the anilides 6 on acid-catalyzed rearrangement, deprotection and cyclisation led to the 2-aryl-2, 3-dihydro-4(1H)-quinolones 16.
