Synthesis, characterization and mechanism of formation of 6-substituted nido-B10H13 decaboranes by the opening reaction of closo-decahydrodecaborate [B10H10]2− cage
Affiliations: Inorganic and Organometallic Coordination Chemistry Laboratory LCIO, Faculty of Sciences I, Lebanese University, Hadath, Lebanon | Doctoral School of Sciences and Technology EDST, Platform of Research for Analytical Sciences and Environment PRASE, Lebanese University, Hadath, Lebanon
Note: [] Corresponding author: Daoud Naoufal, Lebanese University, Faculty of Sciences I, Rafic Hariri University Campus, Inorganic and Organometallic Chemistry Laboratory LCIO, Department of Chemistry and Biochemistry, 4th Floor, Room 404, Lebanon. Tel.: +961 3 893497; Fax: +961 5 461496; E-mails: dnaoufal@ul.edu.lb; professeurchimie@yahoo.fr
Abstract: 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−.
