Reaction of imines 1 with arylidenemalononitriles 2 leads in one step to their corresponding 2-amino-3-cyano-1,4-dihydropyridines 3. The structure of all obtained compounds was confirmed on the basis of their IR, NMR and MS data.
S. Naceur, H. Zantour
imines, enamines, arylidenemalononitriles, 1„4-dihydropyridines
Some novel triazine and pyrimidine derivatives were synthetized by reaction of 1,3- bis (dimethylamino)-1,3-dichloro-2-azapropenylium chloride (azacyanine) with heterocyclic compounds substituted by an amino group.
M. T. Kaddachi, S. Zouari, H. Ben Ammar, J. Cossy, P. Kahn
heterocyclisation, azacyanine, triazine, pyrinndine, amine
Four lignans matairesinol, arctigenin-4'-glucoside, lappaol A and isolappaol A as well as three triterpens β-sitosterol, β-amyrin and taraxasterol have been isolated for the first time from Centaurea furfuracea.
J. A. Fakhfakh, M. Damak
Centaurea furfuracea Coss. et Dur., Asteraceae, lignans, triterpens
The present paper reports the investigation of hydrolysis kinetic of 2,2-dimethyl-2,3-dihydrobenzofuran-7-yl- N-methylcabamate in aqueous media. The determination of 2,2-dimethyl-2,3-dihydrobenzofuranol-7-ol by reversed phase liquid chromatography and spectrophotometric UV titrations, as the adduct of hydrolysis carbamate shows the significant reactivity of the insecticide. The obtained positive entropy ΔS≠ = 73,60 3 mol-1 K-1 and the absence of basic general catalysis indicate an E1cB mechanism involving unimolecular collapse of the carbofuran via a methylisocyanate intermediate. This E1cB process is confirmed by the position of the coordinate (pKa = 10,01 ; log kOH = 1,66) corresponding to the carbofuran point on Brönsted line. The β slope value is -1,10. The Brönsted relation ship is a plot of the rate bimolecular constant logarithm versus the pKa of the conjugate acid of leaving group for a series of substitued N-methylcarbamate which the decomposition mechanism in aqueous media procede via E1cB.
N. Ben Hamida, L. Latrous, S. Sabbah
carbofuran, kinetic, mechanism, HPLC, spectrophotometric UV
A number of 1,n-bis-(4-phenyl-1,5-benzodiazepin-2-oxo-1-yl(alcanes have been prepared by reaction between 4-phenyl-l,5-benzodiazepin-2-one and dihalogenoalcanes X-(CH2)n-X under phase transfert catalysis conditions. Also, we have study the conformational analysis by molecular modelisation of 1,n-bis-(4-phenyl-1,5-benzodiazepin-2-oxo-1yl-)alcanes.
R. Zniber, A. J El Hajjl, R. Achour, M.Z. Cherkaoui, A. Moussaif, M. El Ghoul, D. Guillon
benzodiazepin, conformational analysis, molecular modelisation, alkan dihalogenure
The reaction of the iminoesters with the tosylhydrazine in the presence of cations resin exchange gives exclusively the tosylamidrazones with good yields. The latter were converted into tosyltriazoles when submitted to orthoesters in the presence of acetic acid.
M. Kossentini, F. Chabchoub, Y. Le Bigot, M. Salem
Spectroscopic analysis of the acylant system formed by trichloroacetic acid and acetic anhydride shows the presence of the following species : acetic trichloroanhydridium and acetic anhydridium ions under cyclic chelate shape. The survey of a set of solutions, that variable relative molar fractions, of this acylant system shows that the equilibrium of formation of these ions depends on the initial concentration ratio of the two interactive reagents: [Cl3CCO2H]0 / [(CH3CO)2O]0.
A. Bouchoul, P. Paillous, S. Bouaoud
Acetic anhydride, trichloroacetic acid, mixed anhydride, aryl group
Copper indium diselenide electrodeposition in thin films is studied in an electrolyte consisting of a glycine / glycinium (NH3–CH2–COOH+ / NH2–CH2–COOH) buffer solution. Compared with the currently used sulphuric acid electrolyte, the use of a buffer makes easier the indium insertion, especially when the solution is poorly stirred. This is explained by the fixation of the pH near the electrode that impedes the hydrolysis of In3+ ions.
E. Selmane Bel Hadj Hmida, M. Dachraoui, P. Cowache, J. Vedel
Thin films, electrodeposition, glycine, buffer, CuInSe2 (CIS) current-potential curves, atomic absorption spectroscopy
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