JOURNAL of the Tunisian Chemical Society

serving the Research, the Education and the Industry

Préparation du sclaréolide par ozonolyse du sclaréol. Synthèse de l’Ambrox® en trois étapes

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Sclareolide was obtained in high yield (> 96%) in a one pot reaction from sclareol by ozonolysis and treatment in situ by H2O2/NaOH/CH3CO3H. This commercially interesting product gave Ambrox® in very good yield (Total yield from sclareol > 85%) by reduction and subsequent cyclisation of the intermediary bicyclohomofarnesane 8α-12diol.

A. Fekih, F. Habbachi

Ambrox®, sclareol, sclareolide, ozonolysis

Pages 909-914

Synthèse des biscoumarines en milieu biphasique solide/liquide: 1. Condensation de l’aldéhyde salicylique avec le m-phénylène diacétonitrile

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The condensation of salycilic aldehyde with m-phenylene diacetonitrile, when catalysed by anion-exchange resins, leads selectively to the corresponding biscoumarin or bisiminocoumarin in high yield. A study of the effects of various physicochemical parameters governing the behaviour of the ion exchanger allowed the most favorable reaction conditions to be determined. The best results were obtained using IRA 900 macropores resin, appropriately hydrated. A reaction mechanism involving ionic intermediates is proposed.

H. Ammar, Y. Le Bigot, R. El Gharbi

Ion-exchange resins, Biscoumarins, Salicylic aldehyde

Pages 915-923

Synthèse des N-amidotriazolones: Structure cristalline du 1-phényl-3-éthyl-4-benzamido-1,2,4-triazol-5-one, C17H16N4O2

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The hydrazides 1, react with hydrazonates N-1-ethoxycarbonylated 2 to give 1,2,4-triazol-5-ones 3. The X ray crystal structure of one compound has been analysed and confirms the proposed structure. The C17H16N4O2 is monoclinic P21/n with the following unit cell dimensions a = 13.460(6)Å, b = 7.370(2)Å, c = 15.747(6)Å, β = 96.30(2)°, z = 4, ρx = The average structure was determinated at R = 0.0622 and Rw = 0.2210. Examination of the structure shows isolated dimers of C34H32N8O4 parallel to the c axis : the molecules are connected through intermolecular hydrogen bonds.

A. Rekik, S. Chaabouni, F. Chabchoub, S. Kamoun, M. Salem

Hydrazonates-triazolones, Crystal structure

Pages 925-933

Alcaloïdes des feuilles de Hammada scoparia (Pomel) Iljin

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Extraction and separation of alkaloids from the leaves of Hammada scoparia (Pomel) Iljin have led to the isolation and identification of eight alkaloids : N-methylisosalsoline, carnegine, isosalsoline, N-methylcorydaldine, tryptamine, Nb-methyltiyptamine, 2-methyl -1 ,2,3,4-tetrahydro-β-carboline and leptocladine. The two latter compounds are isolated for the first time from Hammada scoparia.

R. Jarraya, M. Damak

Hammada scoparia, alkaloids, isoquinolines, 2-methy1-1,2,3,4-tetrahydro-β-carboline, leptocladine

Pages 941-948

Cycloaddition dipolaire-1,3 du 2-diazopropane sur des énones α substituées - Synthèse par photochimie de cyclopropylcétones

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The reaction of 2-diazopropane 1 with (E)-disubstituted 3-butene-2-ones 2a-d, at 0°C, gave a 3-acetyl-5,5-dimethyl- Δ1-pyrazolines 3a-d. The photolysis of 3a-d led to the exclusive obtaining of gem-dimethyl cyclopropylketones 4a-d in a stereospecific manner.

J. Lacheb, F. Abdelleoui, M.-T. Martin, A. Khemiss

2-diazopropane, Δ1-pyrazolines, photochemistry, cyclopropane

Pages 949-955

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