A synthesis of 4-aryl quinolin-2(1H)-ones by acidic zeolite promoted intramolecular cyclization of N-aryl amides of 3-arylpropynoic acids

Alkenylation of Arenes and Heteroarenes with Alkynes

“…N -Arylamides, − esters, or thioesters of 3-arylpropynoic acids 568 have been converted into derivatives of quinolone (X = NH), coumarin (X = O), or thiocoumarin (X = S) 569 , respectively, under the action of various acids (e.g., TfOH, − FSO 3 H, H 2 SO 4 , , or acidic zeolites , ) (Scheme ). Significant changes in the substituents of the starting substrates 568 , variations of the acidic agents, the reaction temperature (−75 to 130 °C), and time (0.5 to 100 h) allowed the authors to achieve the highest yields of the target compounds 569 .…”

DFT insights into superelectrophilic activation of α,β-unsaturated nitriles and ketones in superacids

“…9,11,[30][31][32] It is not surprising, therefore, that these and analogous species have been repeatedly proposed as key superelectrophilic 2 intermediates in the corresponding reactions with weak nucleophiles, such as benzene, deactivated aromatics and alkanes. 6,[8][9][10][11][12][13][14][15][16][17][18][19][20][22][23][24][25][26]33 On the other hand, perhaps the most widely proposed candidate for the role of a strong electrophile derived from α,β-enones in superacids is the O,O-diprotonated form 6 (Fig. 4).…”

“…undergo a specific kind of electrophilic activation upon action with strong Brønsted or Lewis acids. 1–25 This allowed involving them in a large variety of Friedel–Crafts type transformations, offering quite appealing synthetic solutions. Fig.…”

“…9,11,30–32 It is not surprising, therefore, that these and analogous species have been repeatedly proposed as key superelectrophilic 2 intermediates in the corresponding reactions with weak nucleophiles, such as benzene, deactivated aromatics and alkanes. 6,8–20,22–26,33…”

Reactions of N,3-diarylpropiolamides with arenes under superelectrophilic activation: synthesis of 4,4-diaryl-3,4-dihydroquinolin-2(1H)-ones and their derivatives

“…Based on our works on the synthesis of 4-arylquinolin-2(1 H )-ones from acetylene compounds under superelectrophilic activation conditions [ 11 – 14 ], we continued to develop some methods for the syntheses of quinoline derivatives. Previously we showed, just in a few examples, that some 3-aryl- N -(aryl)propiolamides reacted with benzene under the action of Brønsted or Lewis superacids affording 4-aryl-4-phenyl-3,4-dihydroquinolin-2(1 H )-ones [ 12 – 13 ].…”