Hydroboration reactions of carboxylic acids using sodium aminodiboranate (NaNH 2 [BH 3 ] 2 , NaADBH) to form primary alcohols were systematically investigated, and the reduction mechanism was elucidated experimentally and computationally. The transfer of hydride ions from B atoms to C atoms, the key step in the mechanism, was theoretically illustrated and supported by experimental results. The intermediates of NH 2 B 2 H 5 , PhCHCHCOOBH 2 NH 2 BH 3 − , PhCHCHCH 2 OBO, and the byproducts of BH 4 − , NH 2 BH 2 , and NH 2 BH 3 − were identified and characterized by 11 B and 1 H NMR. The reducing capacity of NaADBH was found between that of NaBH 4 and LiAlH 4 . We have thus found that NaADBH is a promising reducing agent for hydroboration because of its stability and easy handling. These reactions exhibit excellent yields and good selectivity, therefore providing alternative synthetic approaches for the conversion of carboxylic acids to primary alcohols with a wide range of functional group tolerance.

Boron-containing transition metal materials are new kinds of promising electrode materials for supercapacitors due to their good electrochemical activity, cost-effectiveness, and eco-friendliness. Here, through the oxidation of amorphous porous Ni− Co bimetallic borate nanosheets/C nanoaggregate precursor, a series of Ni−Co−B−O/C nanocomposites are fabricated. By adjusting the oxidation temperatures, the concentration of the oxidized-borate species near the surface was well-tuned. This results in creating different concentrations of the "electron-unsaturated" O atoms, which can accept extra electrons easily and promote the absorption/diffusion of electrolyte ions. Meanwhile, the hierarchically porous characteristic and low-crystallinity structure of the precursor are successfully maintained. Employed as an electrode, the optimized Ni−Co−B−O/C nanocomposite shows a specific capacity of 1139 C g −1 at 1 A g −1 and 83.5% capacitance retention after 2000 cycles. When assembled with reduced graphene oxide into a hybrid supercapacitor, a high energy density of 48.2 W h kg −1 at a power density of 429.8 W kg −1 , high rate capability, and excellent stability were achieved, indicating great application potential in energy storage applications.

Recent research has attracted considerable attention toward N-heterocyclic carbene-coordinated boranes (NHCborane) and their B-substituted derivatives because of their unique characteristics. In the present work, we focused on the syntheses, structures, and reactivities of such types of amine complexes, [NHC•BH 2 NH 3 ]X ((NHC = IPr (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and IMe (1,3-dimethylimidazol-2-ylidene); X = Cl, I, OTf). We have developed a synthetic method to access NHC•BH 2 NH 2 through the reaction of NaH with [IPr•BH 2 NH 3 ]I, which was synthesized by the reaction of IPr•BH 2 I with NH 3 . As a Lewis base, NHC•BH 2 NH 2 could further react with HCl or HOTf to produce the corresponding salts of [IPr•BH 2 NH 3 ] + . IPr• BH 2 NH 2 BH 2 X (X = Cl, I) were synthesized by the reaction of HCl/I 2 with IPr•BH 2 NH 2 BH 3 and then converted to [IPr• BH 2 NH 2 BH 2 •IPr]X (X = Cl, I) by reacting with IPr. The IMe-coordinated boranes reacted quite similarly. The preliminary results revealed that the introduction of the NHC molecule has a considerable impact on the solubility and reactivities of aminoboranes.

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The reactions of sodium amidoborane (NaNH2BH3) with NiBr2 have been investigated, and the results showed that black precipitate 1 including the NiBNHx composites could be obtained. From the aqueous solution of the precipitate 1, the hydrolysis product Ni–B (2) was isolated and characterized. Both the in situ formed precipitate 1 and the hydrolysis product 2 can catalyze the formation of Na­[BH3(NH2BH2)2H]. CoCl2 showed comparable performance with NiBr2. Based on these results, a facile method for the synthesis of Na­[BH3(NH2BH2)2H] has been developed. This work provides insights into studying experimental methods for the synthesis of long B/N chain complexes and developing boron and nitrogen chemistry.