Cyanomethanephosphonates are transformed on imidates α-phosphonated and on phosphonitrils α-bromated respectively, by the alcohol action and the bromine in a basic medium. The treatment of iminoesters and nitrils α-bromated obtained, by the carbonylate derivates, under the conditions of Wittig-Horner reaction, permited the access to the iminoesters α,β-ethylenics and nitrils α,β-ethylenics α-bromated and α-cyano α-phosphoepoxydes
M.A. Oueslati, M. Haddad, A. Belhadj Amor, B. Baccar
Pages: 489-496
α-carboethoxyhydrazones 1 react with orthoesters to give α-carboethoxyhydrazonates 2. Treatment of these hydrazonates with primary amines yields to α-amidohydrazonates 3 (when the amines are aliphatics) and to 4,5-dihydro-1.2.4 triazin-5-ones 4 (aromatic amines).
M.L. Benkhoud, B. Baccar
Pages: 497-503
Alkyl N-acylbenzimidates and phenylacetimidates react with alcohols at room temperature to give the corresponding conjugate products : N-(aryl or benzyl dialcoxy methyl) amides, in good yields.
B. Hajjem, A. Harizi, B. Baccar
Pages: 505-511
Treatment of alkyl N-arylacetimidates consecutively by L.D.A. then by electrophilic reagents constitutes an efficient way to yield functionalized iminoesters.
H. M'rabet, S. M'hirsi, H. Zantour, B. Baccar
Pages: 513-521
The synthesis of benzo-1,4-dioxane by reaction of the 1,2-dichloroethane with the pyrocatechol takes place in attendance of polar solvants that are sometimes very expensive. In this work, the same synthesis has been improved speed and output by phase transfert catalysis.
B. Hamada, M. Safar, O. Kaddour, A. Boukherissa
Pages: 523-532
Polymethylhydrosiloxane (PMHS) was reacted by modification with 1-hexanol, 1-hexene, 1,6-hexanediol and 1,5-hexadiene. The reaction with the 1-hexanol and 1-hexene was studied in the liquid phase by NMR and infrared. The use of bifunctional reactants such as 1,6-hexanediol and 1,5-hexadiene leads to the formation of polymeric transparent gels that have been characterized by 29Si, 13C MAS-NMR and infrared. The difference of the crosslinking groups for the two systems, Si-O-C versus Si-C bonds, influences the stability of the polymeric materials.
R. Kalfat, M. Gharbi, H. Zarrouk, F. Babonneau
Pages: 533-543
A new mercury complex CH3NH3HgClBr2 was prepared with partial substitution of chlorine by bromine in the ferroelectric compound CH3NH3HgCl3. The complex has been characterized by different physico-chemical methods. X-ray studies of CH3NH3HgClBr2 showed an isomorphous character with the paraelectric phase of CH3NH3HgCl3. A structure for CH3NH3HgClBr2 is proposed. Raman spectra of polycrystalline samples of CH3NH3HgClBr2, CH3NH3HgCl3 and CH3NH3HgBr3 have been recorded. Assignments of most the observed bands are proposed. A comparative study of the spectra confirms the proposed structure.
R. Ben Hassen, A. Ben Salah
Pages: 545-554
In this work we present the choice and acquisition of thermodynamics data of the H2O-MgCl2.6H2O-LiCl ternary system in order to study the possibility of its utilisation in absorption cycles. The results are shown in tables and/or in diagramms. The analysis of these results shows that the new system has a heat pump effect similar to the both systems H2O-CaCl2-LiCI and H2O-LiBr in a fixed concentration and temperature range.
B. Chaouachi, T. Khir, A. Ben Brahim
Pages: 555-564
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