The Mechanism of Fries Rearrangement and Acylation Reaction in Polyphosphoric Acid.

1993 ◽  
Vol 66 (1) ◽  
pp. 135-139 ◽  
Author(s):  
Hashem Sharghi ◽  
Hossien Eshghi
Keyword(s):  
Polyphosphoric Acid ◽  
Acylation Reaction ◽  
Fries Rearrangement

The Preparation and Characterization of Polybenzoxazole Copolymerized with Multiwalled Carbon Nanotube via Direct Friedel-Crafts Acylation

2014 ◽  
Vol 989-994 ◽  
pp. 560-563
Author(s):  
Yong Chen ◽  
Jun Qian ◽  
Qi Xin Zhuang ◽  
Zhe Wen Han
Keyword(s):  
Carbon Nanotube ◽  
Polyphosphoric Acid ◽  
Multiwalled Carbon Nanotube ◽  
X Ray Diffraction ◽  
Acylation Reaction ◽  
Multiwalled Carbon ◽  
Sem Images ◽  
X Ray ◽  
Electronic Microscope

Multiwalled carbon nanotube (MWCNT) was subjected a copolymerization reaction with 4, 6-diaminoresorcinol salt (DAR•2HCl) and terephthalic acid (TA) in polyphosphoric acid (PPA) by Friedel-Crafts acylation reaction without any acid treatment or modification. The structure and morphology of the as-prepared poly (p-phenylene benzobisoxazole) (PBO)/MWCNT nanocomposites were characterized by X-ray diffraction (XRD) and scanning electronic microscope (SEM). The SEM images indicated that MWCNTs can disperse in PBO matrix uniformly without agglomeration and MWCNTs have been introduced into PBO matrix by covalent bonding via Friedel-Crafts acylation between MWCNTs and TA.

scholarly journals An efficient access to the synthesis of novel 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H)-one derivatives

2012 ◽  
Vol 8 ◽  
pp. 1849-1857 ◽  
Author(s):  
Wentao Gao ◽  
Guihai Lin ◽  
Yang Li ◽  
Xiyue Tao ◽  
Rui Liu ◽  
...  
Keyword(s):  
Polyphosphoric Acid ◽  
Reaction Times ◽  
Easy Access ◽  
Substituted Phenols ◽  
Acylation Reaction ◽  
One Pot ◽  
Cerium Ammonium Nitrate ◽  
Starting Compound ◽  
Efficient Access ◽  
Cerium Ammonium

An efficient access to the tetracyclic-fused quinoline systems, 12-phenylbenzo[6,7]oxepino[3,4-b]quinolin-13(6H)-one derivatives 4a–l, is described, involving the intramolecular Friedel–Crafts acylation reaction of 2-(phenoxymethyl)-4-phenylquinoline-3-carboxylic acid derivatives 3a–l aided by the treatment with PPA (polyphosphoric acid) or Eaton’s reagent. The required starting compound (2) was obtained by Friedländer reaction of 2-aminobenzophenone (1) with 4-chloroethylacetoacetate by using CAN (cerium ammonium nitrate, 10 mol %) as catalyst at room temperature. The substrates 3a–l were prepared through one-pot reaction of ethyl 2-(chloromethyl)-4-phenylquinoline-3-carboxylate (2) and substituted phenols. Our developed strategy, involving a three-step route, offers easy access to tetracyclic-fused quinoline systems in short reaction times, and the products are obtained in moderate to good yields.

4-Hydroxy Pyridinium Triflate@SiO2 Nanoparticles as a Novel Efficient Catalyst for Fries Rearrangement of Aryl Esters with High Selectivity

2020 ◽  
Vol 17 (8) ◽  
pp. 654-660
Author(s):  
Shermineh Sadat Ghalehbandi ◽  
Dadkhoda Ghazanfari ◽  
Sayed Ali Ahmadi ◽  
Enayatollah Sheikhhosseini
Keyword(s):  
High Selectivity ◽  
Sio2 Nanoparticles ◽  
High Yield ◽  
Synthetic Method ◽  
Functionalized Silica ◽  
Efficient Catalyst ◽  
Fries Rearrangement ◽  
Free Condition ◽  
Solvent Free Condition ◽  
Work Up

Introduction: We developed a simple, fast and new method for the Fries rearrangement of aryl esters. Materials and Methods: 4-Hydroxy pyridinium triflate functionalized silica is a very efficient, reusable and economically available catalyst for the Fries rearrangement in solvent-free condition and under microwave irradiation. Results and Discussion: Also, a notable selectivity was observed in the presence of 4-hydroxy pyridinium triflate functionalized silica. Conclusion: Selectivity, shorter reaction time, high yield, and easy work-up are advantages of this synthetic method.

Fluorinated tricyclic neuroleptics with prolonged action: 8-Methoxy, 8-ethoxy, 8-ethylthio and 8-hydroxy derivatives of 3-fluoro-10-(4-methylpiperazino)-10,11-dihydrodibenzo[b,f]thiepin

1982 ◽  
Vol 47 (5) ◽  
pp. 1382-1391 ◽  
Author(s):  
Jiří Jílek ◽  
Josef Pomykáček ◽  
Jiřina Metyšová ◽  
Miroslav Protiva
Keyword(s):  
Acetic Acid ◽  
Polyphosphoric Acid ◽  
Prolonged Action ◽  
Substitution Reactions ◽  
Methoxy Derivative ◽  
Chloro Derivatives ◽  
Boron Tribromide ◽  
Derivatives Of ◽  
Central Depressant ◽  
Boiling Toluene

Acids IIa-c were prepared by reactions of (4-fluoro-2-iodophenyl)acetic acid with 4-methoxythiophenol, 4-ethoxythiophenol and 4-(ethylthio)thiophenol and cyclized with polyphosphoric acid in boiling toluene to dibenzo[b,f]thiepin-10(11H)-ones IIIa-c. Reduction with sodium borohydride afforded the alcohols IVa-c which were treated with hydrogen chloride and gave the chloro derivatives Va-c. Substitution reactions with 1-methylpiperazine resulted in the title compounds Ia-c out of which the methoxy derivative Ia was transformed by demethylation with boron tribromide to the phenol Id. Compounds Ia-d are very potent neuroleptics exhibiting a clear prolongation of the central depressant and some prolongation of the cataleptic activity.

Fluorinated analogues of tricyclic neuroleptics: 6,9-difluoro derivative of 10-(4-methylpiperazino)-10,11-dihydrodibenzo[b,f]thiepin

1980 ◽  
Vol 45 (10) ◽  
pp. 2688-2694 ◽  
Author(s):  
Irena Červená ◽  
Marta Hrubantová ◽  
Emil Svátek ◽  
Jiří Holubek ◽  
Miroslav Ryska ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Title Compound ◽  
Substitution Reaction ◽  
Polyphosphoric Acid ◽  
Satisfactory Yield ◽  
Chloro Derivative ◽  
Cns Activity

The acid VI, obtained from 2,5-difluorothiophenol (IV) and (2-iodophenyl)acetic acid, afforded by cyclization with polyphosphoric acid 6,9-difluorodibenzo[b,f]thiepin-10(11H)-one (VII) in a satisfactory yield. Two further steps led to the chloro derivative X giving by a substitution reaction with 1-methylpiperazine the title compound III. This substance exhibits some 10% incoordinating activity of the unsubstituted compound I and an indication of cataleptic activity, in contrast to the inactive analogous dichloro compound II. The bulky atom of chlorine in the vicinity of the methylpiperazine residue interferes evidently with the CNS activity; the influence of the atom of fluorine is much less pronounced in this line.

Friedel-Crafts acylation reaction over hierarchical Y zeolite modified through surfactant mediated technology

2021 ◽  
pp. 111167
Author(s):  
Angela Martins ◽  
Vera Neves ◽  
João Moutinho ◽  
Nelson Nunes ◽  
Ana P. Carvalho
Keyword(s):  
Y Zeolite ◽  
Acylation Reaction
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