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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. [ABSTRACT FROM AUTHOR]

The synthesis of new 6-LB10H13 (L = ligand) derivatives of decaborane B10H14 with different ligands was achieved by the opening cage reaction of closo-decahydrodecaborate (NH4)2B10H10 in the presence of a strong acid (HNO3 or H2SO4) in organic solvents (hexane or benzene derivatives). This reaction was performed by varying different factors: the acid strength, the solvent polarity, the equivalent amounts of (NH4)2B10H10 with respect to the acid used (1/4 or 1/6) and the reaction time (30 minutes to 24 hours). Nitric acid forced hexane solvent to play the role of ligand whereas sulfuric acid did not. The reaction of (NH4)2B10H10 with HNO3 in hexane produced 6-(C6H13)B10H13 and [B9H13NO3]-. The reaction of (NH4)2B10H10 with H2SO4 in aromatic solvent L (benzene, toluene, o-xylene and m-xylene) produced 6-LB10H13 and 6-(HO3SO)B10H13 as major products with B6H10 and [B9H14]- as minor products. All these derivatives were characterized by 11B NMR, 1H NMR, 13C NMR and negative ESI. This study elucidated some facts and ideas that were not clear concerning the mechanism of opening reaction of closo-[B10H10]2-. [ABSTRACT FROM AUTHOR]