scholarly journals Synthesis of New Pyrazoline - Phenoxathiin Derivatives

2013 ◽  
Vol 10 (2) ◽  
pp. 405-419
Author(s):  
Baghdad Science Journal

Phenoxathiin was prepared by the reaction of diphenyl ether with sulfur in the presence of anhydrous aluminum chloride. This work comprised the synthesis of new phenoxathiin derivatives containing heterocyclic moieties. These heterocyclic compounds were synthesized in three groups. The first group was made up of 2-(oxoalken-1-yl) phenoxathiin derivatives (3a-3j) obtained from the reaction of 2-acetylphenoxathiin with different aromatic aldehyde in the presence of sodium hydroxide. The other two groups involved compounds produced from the reaction of (3a-3j) with hydrazine hydrate in acetic acid to get 2-(1-acetyl pyrazolin-3-yl) phenoxathiin derivatives (4a-4j), and phenyl hydrazine in the presence of piperidine to afford 2-(1-phenyl pyrazolin-3-yl) phenoxathiin derivatives (5a-5j). All these compounds of two groups above were substituted in position (5) in pyrazoline ring with different aryl groups according to aromatic aldehyde used in the preparation of the first group series compounds.

1966 ◽  
Vol 44 (17) ◽  
pp. 2009-2014 ◽  
Author(s):  
R. T. Coutts ◽  
J. B. Edwards

4-(2-Nitrobenzylidene)-2-pyrazolin-5-ones (I) were best prepared by heating o-nitrobenzaldehyde and 2-pyrazolin-5-ones in acetic anhydride containing fused sodium acetate (cf. Erlenmeyer azlactone synthesis). Pyrazolones of type I were reductively cyclized with cyclohexene and palladium–charcoal, and gave 3a,4,9,9a-tetrahydro-9-hydroxy-1H-pyrazolo-[3,4-b]quinolines (II) which, as expected, were amphoteric compounds. Of the three other methods of reduction used in this study, two (zinc and acetic acid; sodium borohydride and palladium–charcoal) were capable of producing pyrazoloquinolines, but were less reliable. The other method employed (hydrazine hydrate and palladium–charcoal) caused degradation of the pyrazolone molecule in the two cases examined, and in both, bis(2-aminobenzylidene) hydrazine (V) was the reduction product isolated.


1980 ◽  
Vol 35 (10) ◽  
pp. 1310-1312 ◽  
Author(s):  
El-Sayed Afsah ◽  
Fathy A. Amer ◽  
Mohamed A. Metwally ◽  
Mohamed T. El-Zimaity

Abstract Treatment of diethyl 1,4-cyclohexanedione-2,5-dicarboxylate (1) with hydrazine hydrate in glacial acetic acid afforded the diazobicycloocatdienedicarboxylate (2) and the azine (3). On the other hand, condensation of 1 with benzenesulphonylhydrazide in ethanolic solution gave the indazole derivative (4). Interaction of 1 with urea or hydroxyl-amine afforded the tetrahydropyrimidoquinazolinone (5) and the tetrahydrobenzodi-isoxazolone (6), respectively. Treatment of 1 with aniline gave the mono-anil (7) which, when subjected to Japp-Klingemann reaction with p-anisidine gave the dihydrazonoanil (8) and their condensation with benzidine in acetic acid gave the hydrazonoketoester (9). On the other hand condensation of 7 with hydrazine hydrate in ethanolic solution afforded the azobis (5-anilinoterephthalate) (10) and the hexahydrobenzodipyrazolone (11).


2010 ◽  
Vol 29 (1) ◽  
pp. 87 ◽  
Author(s):  
Hatem E. Gaffer ◽  
Mohamed A. E. Khalifa ◽  
Shaima F. El-Bially ◽  
Mohamed A. Metwally

Condensation of 2,4-diacarboethoxy-5-hydroxy-3-(4-methoxyphenyl)-5-methyl cyclohexanone (1) with equimolar amounts of hydrazine hydrate and phenyl hydrazine afforded the corresponding 2H-indazole-5-carboxylates 2a and 2b, respectively. Coupling of 2 with diazotized aromatic amines furnished the corresponding azo compounds 3a n. When compound 1 was subjected to the Japp-Klingemann reaction in alkaline medium with diazotized aromatic amines furnished the corresponding hydrazones 4a-g. The treatment of 4a-g with phenyl hydrazine in acetic acid allows the isolation of arylhydrazono derivatives 5a-g. The structures of the dyes were established using analytical and spectral data. Evaluation of the technical properties and color assessment of the dyes were done.


2020 ◽  
Vol 17 ◽  
Author(s):  
Ravi Bansal ◽  
Pradeep K. Soni ◽  
Neha Gupta ◽  
Sameer S. Bhagyawant ◽  
Anand K. Halve

Aims: In this article we have developed an eco-friendly one-pot multi-component reaction methodology was employed for the green synthesis of functionalized pyrazole derivatives viz cyclo-condensation of aromatic aldehydes, ethyl acetoacetate and phenyl hydrazine and/or hydrazine hydrate in the presence of cetyltrimethylammoniumbromide (CTAB) at 90°C temperature in aqueous medium. Method: In the present protocol we developed a green method for the synthesis of functionalized pyrazole derivatives through one-pot, multi-component cyclo-condensation of aromatic aldehydes, phenyl hydrazine or hydrazine hydrate and ethyl acetoacetate using cetyltrimethylammoniumbromide (CTAB) as a catalyst in water as solvent. Our methodology confers advantages such as short reaction time, atom economy, purification of product without using column chromatographic and hazardous solvent. The reaction is being catalyzed by cetyltrimethylammoniumbromide (CTAB) and thus products are formed under the green reaction conditions. Results: Initially the reaction of benzaldehyde and phenylhydrazine with ethyl acetoacetate was carried out in water at room temperature in the absence of the catalyst; no product was obtained after 24 h (Table 1 entry 1). When the reaction was carried out using L-proline as catalyst in ethanol at 70°C the yield of product was 20. Conclusion: This research not only provides a green and efficient method for the synthesis of sulfinic esters but also shows new applications of electrochemistry in organic synthesis. We consider that this green and efficient synthetic protocol used to prepare sulfinic esters will have good applications in future. In conclusion, we have developed successfully a green and efficient one-pot multi-component methodology for the synthesis of substituted pyrazoles using CTAB as a catalyst in water as solvent with excellent yields. Purifications of compounds were achieved without the use of traditional chromatographic procedures. This methodology has advantages of operational simplicity, clean reaction profiles and relatively broad scope which make it more attractive for the diversity oriented synthesis of these heterocyclic libraries. In this methodology we suggest the further alternative possibility for formation of substituted pyrazoles. The compound 7h can be used as an anticancer drug in pharma industry.


2019 ◽  
Vol 16 (6) ◽  
pp. 527-543 ◽  
Author(s):  
Pedro M.E. Mancini ◽  
Carla M. Ormachea ◽  
María N. Kneeteman

During the last twenty years, our research group has been working with aromatic nitrosubstituted compounds acting as electrophiles in Polar Diels-Alder (P-DA) reactions with different dienes of diverse nucleophilicity. In this type of reaction, after the cycloaddition reaction, the nitrated compounds obtained as the [4+2] cycloadducts suffer cis-extrusion with the loss of nitrous acid and a subsequent aromatization. In this form, the reaction results are irreversible. On the other hand, the microwave-assisted controlled heating become a powerful tool in organic synthesis as it makes the reaction mixture undergo heating by a combination of thermal effects, dipolar polarization and ionic conduction. As the Diels-Alder (D-A) reaction is one of the most important process in organic synthesis, the microwave (MW) irradiation was applied instead of conventional heating, and this resulted in better yields and shorter reaction times. Several substituted heterocyclic compounds were used as electrophiles and different dienes as nucleophiles. Two experimental situations are involved: one in the presence of Protic Ionic Liquids (PILs) as solvent and the other under solvent-free conditions. The analysis is based on experimental data and theoretical calculations.


2013 ◽  
Vol 9 ◽  
pp. 8-14 ◽  
Author(s):  
Yan Sun ◽  
Jing Sun ◽  
Chao-Guo Yan

A fast and convenient protocol for the synthesis of novel spiro[dihydropyridine-oxindole] derivatives in satisfactory yields was developed by the three-component reactions of arylamine, isatin and cyclopentane-1,3-dione in acetic acid at room temperature. On the other hand the condensation of isatin with two equivalents of cyclopentane-1,3-dione gave 3,3-bis(2-hydroxy-5-oxo-cyclopent-1-enyl)oxindole in high yields. The reaction mechanism and substrate scope of this novel reaction is briefly discussed.


1972 ◽  
Vol 25 (10) ◽  
pp. 2107 ◽  
Author(s):  
GB Deacon ◽  
GD Fallon

Bismuth triarenesulphinates, Bi(02SR)3 [R = Ph, p-MeC6H4, p-ClC6H4, 2,4,6-(Me2CH)3C6H2, and p-MeCONHC6H4], have been prepared by reaction of bismuth triacetate with the appropriate arenesulphinio acids in glacial acetic acid, and the first two compounds have also been obtained by reaction of triphenyl-bismuth with the appropriate mercuric arenesulphinates. The sulphur-oxygen stretching frequencies of the bismuth sulphinates are indicative of O-sulphinate coordination, and the compounds are considered to be polymeric with bridging O-sulphinate groups and six-coordinate bismuth. Thermal decomposition of Bi(O2SR)3 (R = Ph, p-MeC6H4, or p-CIC6H4) under vacuum gave the corresponding triarylbismuth compounds and sulphur dioxide, the preparation of tri-p-chlorophenylbismuth being accompanied by formation of di-p-chlorophenyl sulphone and S-p-chlorophenyl p-chlorobenzenethiosulphonate. Pyrolysis of the other triarenesulphinates did not yield organobismuth compounds.


Sign in / Sign up

Export Citation Format

Share Document