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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. [ABSTRACT FROM AUTHOR]

A facile synthesis of heavy alkali metal octahydrotriborates (MB3H8; M=K, Rb, and Cs) has been developed. It is simply based on reactions of the pure alkali metals with THF⋅BH3, does not require the use of electron carriers or the addition of other reaction media such as mercury, silica gel, or inert salts as for previous procedures, and delivers the desired products at room temperature in very high yields. However, no reactions were observed when pure Li or Na was used. The reaction mechanisms for the heavy alkali metals were investigated both experimentally and computationally. The low sublimation energies of K, Rb, and Cs were found to be key for initiation of the reactions. The syntheses can be carried out at room temperature because all of the elementary reaction steps have low energy barriers, whereas reactions of LiBH4/NaBH4 with THF⋅BH3 have to be carried out under reflux. The high stability and solubility of KB3H8 were examined, and a crystal structure thereof was obtained for the first time. Sublime reactivity: Unsolvated MB3H8 (M=K, Rb, and Cs) salts were prepared by reactions of the respective pure alkali metals with THF⋅BH3 in high yield at room temperature, and the structure of unsolvated KB3H8 was elucidated. The proposed reaction mechanisms are based on experimental and theoretical results. It was found that the physical properties of the alkali metals play a crucial role. [ABSTRACT FROM AUTHOR]

A facile synthesis of heavy alkali metal octahydrotriborates (MB3H8; M=K, Rb, and Cs) has been developed. It is simply based on reactions of the pure alkali metals with THF⋅BH3, does not require the use of electron carriers or the addition of other reaction media such as mercury, silica gel, or inert salts as for previous procedures, and delivers the desired products at room temperature in very high yields. However, no reactions were observed when pure Li or Na was used. The reaction mechanisms for the heavy alkali metals were investigated both experimentally and computationally. The low sublimation energies of K, Rb, and Cs were found to be key for initiation of the reactions. The syntheses can be carried out at room temperature because all of the elementary reaction steps have low energy barriers, whereas reactions of LiBH4/NaBH4 with THF⋅BH3 have to be carried out under reflux. The high stability and solubility of KB3H8 were examined, and a crystal structure thereof was obtained for the first time. [ABSTRACT FROM AUTHOR]

A facile synthesis of heavy alkali metal octahydrotriborates (MB3H8; M=K, Rb, and Cs) has been developed. It is simply based on reactions of the pure alkali metals with THF⋅BH3, does not require the use of electron carriers or the addition of other reaction media such as mercury, silica gel, or inert salts as for previous procedures, and delivers the desired products at room temperature in very high yields. However, no reactions were observed when pure Li or Na was used. The reaction mechanisms for the heavy alkali metals were investigated both experimentally and computationally. The low sublimation energies of K, Rb, and Cs were found to be key for initiation of the reactions. The syntheses can be carried out at room temperature because all of the elementary reaction steps have low energy barriers, whereas reactions of LiBH4/NaBH4 with THF⋅BH3 have to be carried out under reflux. The high stability and solubility of KB3H8 were examined, and a crystal structure thereof was obtained for the first time. Sublime reactivity: Unsolvated MB3H8 (M=K, Rb, and Cs) salts were prepared by reactions of the respective pure alkali metals with THF⋅BH3 in high yield at room temperature, and the structure of unsolvated KB3H8 was elucidated. The proposed reaction mechanisms are based on experimental and theoretical results. It was found that the physical properties of the alkali metals play a crucial role. [ABSTRACT FROM AUTHOR]

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The reactivity of sodium amidoborane (NaNH2BH3) as a Brønsted and Lewis base was studied systematically. The [NH2BH3]- anion can act as a proton acceptor or a hydride donor in different types of reactions. In reactions with very weak Brønsted acids such as cyclopentadiene, ammonia, and pyrazole, the [NH2BH3]- anion acts as a proton acceptor through the lone pair on N. The reactions of [NH2BH3]- with stronger Brønsted acids are complicated. In the reaction with ammonium chloride or acetic acid, [NH2BH3]- accepts a proton, reforming NH3BH3. However, in the reaction with HCl or methanol, N-B bond cleavage occurs. [NH2BH3]- can also donate hydride in some reactions. The possible mechanisms of these reactions are discussed. [ABSTRACT FROM AUTHOR]

The reactivity of sodium amidoborane (NaNH2BH3) as a Brønsted and Lewis base was studied systematically. The [NH2BH3]- anion can act as a proton acceptor or a hydride donor in different types of reactions. In reactions with very weak Brønsted acids such as cyclopentadiene, ammonia, and pyrazole, the [NH2BH3]- anion acts as a proton acceptor through the lone pair on N. The reactions of [NH2BH3]- with stronger Brønsted acids are complicated. In the reaction with ammonium chloride or acetic acid, [NH2BH3]- accepts a proton, reforming NH3BH3. However, in the reaction with HCl or methanol, N-B bond cleavage occurs. [NH2BH3]- can also donate hydride in some reactions. The possible mechanisms of these reactions are discussed. [ABSTRACT FROM AUTHOR]