Study of the controlled temperature reaction between closo-decahydrodecaborate and alcohols in H₂SO₄ medium

Article type: Research Article

Authors: Laila, Zahra^{a; b; c} | Abi-Ghaida, Fatima^{a; b; c} | Al Anwar, Suzan^{a; b} | Yazbeck, Ogaritte^{a; b} | Jahjah, Rabih^{a; b} | Aoun, Riman^{a; b} | Tlais, Sami^d | Mehdi, Ahmad^c | Naoufal, Daoud^{a; b; *}

Affiliations: [a] Laboratoire de Chimie de Coordination Inorganique et Organométallique LCIO, Université Libanaise, Faculté des Sciences I, Hadath, Liban | [b] Ecole Doctorale en Sciences et Technologie EDST, PRASE, Université Libanaise, Faculté des Sciences I, Hadath, Liban | [c] Institut Charles Gerhardt, UMR 5253, Université Montpellier 2, Place E. Bataillon, Montpellier Cedex 5, France | [d] Lebanese International University, Beirut, Lebanon

Correspondence: [*] Corresponding author: Daoud Naoufal, Lebanese University, Rafic Hariri University campus, Faculty of Sciences I,Department of Chemistry and Biochemistry, Inorganic and Organometallic Coordination Chemistry Laboratory LCIO, Beirut, Lebanon. Tel.: +96 138 93497; Fax: +96 154 61496; [email protected]

Abstract: The reactions of the ammonium salt of closo-decahydrodecaborate (NH4)2B10H10 with alcohols were studied in concentrated sulfuric acid medium. Alcohols ROH (R = CH3, C2H5, C3H7, iso-C3H7, C4H9, 2-C4H9, ter-C4H9, C5H11) played the role of solvent and ligand, simultaneously. These Electrophile Induced Nucleophilic Substitution Reactions were conducted at two different temperatures (25°C or reflux) in atmospheric air and produced [2-B10H9OR]2 −, [2,7(8)-B10H8(OR)2]2– and/or [B10H7(OR)3]2–. The rate of the reaction and the nature of the product formed depended on the temperature, on the alcohol, and on the reaction duration. The reactions at 25°C, if proceeded, produced mainly the monoalkoxy derivative, [2-B10H9OR]2–. For the longer chain alcohols (4 carbons and above) the increase in the reaction duration and the temperature resulted in higher substitution, thus producing the dialkoxy [2,7(8)-B10H8(OR)2]2– and trialkoxy [B10H7(OR)3]2– derivatives. Meanwhile only the monoalkoxy [2-B10H9OR]2– plus the dialkyloxonium [2-B10H9OR2] − derivatives were produced with the shorter alcohols (1 to 3 carbons) at refluxing temperature. All these derivatives were isolated in their pure forms on DEAE-cellulose column with adequate yields, and characterized by 11B, 13C, 1H NMR, negative ESI and TLC.

Keywords: Decahydrodecaborate, boron hydride, boron compound, alkoxy derivatives

DOI: 10.3233/MGC-150173

Journal: Main Group Chemistry, vol. 14, no. 4, pp. 301-312, 2015