Synthesis and Dehydrogenation of Organic Salts of a Five‐Membered B/N Anionic Chain, a Novel Ionic Liquid

We have synthesized the tetrabutylammonium ([Bu4N]+), tetraethylammonium ([Et4N]+), guanidinium ([C(NH2)3]+), and methylguanidinium ([C(N3H5CH3)]+) salts of the [BH3(NH2BH2)2H]− anion, a five‐membered B/N anionic chain, in high yields by the metathesis reactions of Na[BH3(NH2BH2)2H] with the corresponding halides and characterized them by NMR (11B, 11B{1H}, 1H, 1H{11B}, 13C), IR, elemental analysis, TGA‐DSC, and TGA‐MS. These complexes behave like ionic liquids (ILs), in which the melting point of the [Bu4N][BH3(NH2BH2)2H] is the lowest (−51 °C). The dehydrogenation of these ILs have been studied through the thermal decomposition and catalytic hydrolysis in aqueous solution using the noble or non‐noble metals or their salts as catalysts, and the results indicate that these ILs of five‐membered B/N anionic chain are promising hydrogen storage materials. We have synthesized four ILs of [BH3(NH2BH2)2H]− for the first time in which the melting point of [Bu4N][BH3(NH2BH2)2H] is −51 °C. The dehydrogenations of these ILs have been studied through thermal decomposition and catalytic hydrolysis. Different catalysts have been examined and it is found that RuCl3 has the best catalytic activity. This work provides insights into studying the ILs of [BH3(NH2BH2)2H]− and developing boron chemistry.