The phase transfer catalysis (PTC) process involving solid-liquid systems has been applied to the synthesis of new polyesters containing furan moieties by polycondensation of various alkylidene-bis(2-furoic acid) salts with dibromo compounds. The influence of several reaction parameters such as the nature of liquid phase, temperature, reaction time and the nature and concentration of catalyst was investigated. The polyesters were characterized in terms of backbone structure, molecular weights and thermal stability, showing that the solid-liquid PTC method is very well-suited to the preparation of such polyesters.
S. Abid, S. Dali, R. El Gharbi
polyesters, phase transfer catalysis, furanic polymers
Chemical investigation of Centaurea furfuracea afforded two lignans: (-)-trachelogenin and tracheloside, two flavonoids: acacetin and jaceosidin and a carbohydrate: sucrose. The latter was isolated as an acetate. All of these compounds have been isolated for the first time from this plant. Their structures have been elucidated by spectroscopic methods: (Mass, UV, IR, NMR 1H, 13C, H-H COSY, HMQC, HMBC and NOESY).
J.A. Fakhfakh, M.T. Martin, M. Damak
Centaurea furfuracea Coss. et Dur., lignans, flavonoids, carbohydrate
In this article we describe the reaction of o-phenylenediamine with 4-arylidene-2-methyl(phenyl)oxazolin-5-one in n-butanol. Various results are obtained depending from the nature of substituant in position 2 : i) for methyl we obtain quinoxaline 3 and benzimidazole 4 structures, ii) for phenyl the reaction offered fonctionnalized olefins 6 and arylidene benzimidadazole 7 in addition of compounds 3, 4 and 5. The structure of different compounds is determined by spectroscopic methods.
M. Jellal, Y. Ramli, A. Moussaif, Y. Kandri Rodi, J. Fifani, E. M. Essassi, M. Pierrot
quinoxaline, benzimidazole, functional olefin
This paper describes the study of the arylation of isoprene, (E)-penta-1,3-diene and 2,3-dimethylbuta-1,3-diene with palladium complexes. In every case, the regioselectivity of the reaction is established on 1H-NMR data. Mechanisms are proposed in order to explain the results obtained for the five reactions.
K. Saïd, Y. Moussaoui, R. Ben Salem
arylation, diènes conjugués, complexes palladiés, mécanismes réactionnels
The action of 1-F-octyl-2-fluoroethanol on the aroxy(alkoxy)sulfonyl isocyanates gives corresponding carbamates. The reaction takes place in anhydrous ether at 0°C.
H. Rmedi, M. Beji, A. Baklouti
2-dialkylaminomethylpropenenitriles 1 react with alkyl mercaptoacetates and mercaptopropionates to give respectively dihydrothiophenes 3 and thiopyranones 5. From a mechanistic view point, the reaction leads to thiopyranones 5, proceeds by the intermediary β-mercaptoester 4 which was isolated.
K. Dridi, M.L. El Efrit, H. Zantour
Mercaptoacétate, mercaptopropionate, dihydrothiophène, thiopyranone
Six novel diacetamido-crown ethers have been prepared in one pot synthesis by the reaction of their corresponding nitro derivatives with a mixture of acetic acid, iron powder and acetic anhydrid. The acetamido function was fixed on the aromatic rings. The substituted compounds were characterized by: IR, 1H NMR, 13C NMR, DSC, UV, mass spectrometry (S.M.) and elemental analysis. Some of these diacetamido-crown ethers were screened for their alkaline cation complexation.
A. Ben Hadj Amor, A. Ouerghui, M. Bellassoued, F. Meganem
Synthesis, Diacetamido-crown ethers, Alkaline cation complexation
Phase transfer catalysis using a liquid / liquid process has been applied to the synthesis of a series of furanic polyhydrazides. The effects of several parameters (organic solvent, temperature, reaction time, ratio [NaOH] / [dihydrazide], ratio of monomers and nature of CTP) on the interfacial polycondensation reaction of 2,2'-bis(2,5- hydrazylfuryl) propane and adipoyl chloride are discussed. The inherent viscosity values of the resulting polyhydrazides are much higher than those obtained by solution polycondensation.
A. Afli, S. Abid, R. El Gharbi, A. Gandini
Phase transfer catalysis, Furanic poyhydrazides, Interfacial polycondensation
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