Institute of Condensed Matter and Nanosciences, Université Catholique de Louvain, 1348Louvain-la-Neuve, Belgium.
Hefei General Machinery Research Institute, Hefei230031, China.
Inorg Chem. 2023 Feb 6;62(5):2153-2160. doi: 10.1021/acs.inorgchem.2c03810. Epub 2023 Jan 24.
Metal dodecaborates (MBH) are a versatile class of materials used in polymer chemistry and cancer treatment and are promising candidates as electrolytes for solid-state batteries. However, a general and scalable approach has not yet been developed for producing high-purity BH derivatives. In this work, we report a simple, efficient, and environmentally benign solvothermal method to prepare diffraction and B NMR pure NaBH (85% yield) and KBH (84% yield). This new synthetic approach is based on the use of the borane dimethyl sulfide complex (DMS·BH) and borohydrides (NaBH, KBH) heated at different temperatures in diglyme in an autoclave. It was found that high-purity NaBH·diglyme solvate is obtained via an intermediate formation of BH, BH, and BH, which are all soluble in diglyme. Heating under vacuum is shown to be efficient for removing the coordinated diglyme, allowing the formation of unsolvated NaBH. Autoclave synthesis starting from KBH directly yields solvent-free KBH, and ball-milling KBH prior to the synthesis enabling us to significantly improve the final yield. The new synthetic method paves the way for large-scale synthesis of MBH derivatives, enabling to envisage a wider scope of practical applications.
金属十二硼烷（MBH）是一类在聚合物化学和癌症治疗中用途广泛的材料，它们是作为固态电池电解质的有前途的候选物。然而，目前还没有开发出一种通用且可扩展的方法来生产高纯度 BH 衍生物。在这项工作中，我们报告了一种简单、高效和环境友好的溶剂热法，用于制备衍射和 B NMR 纯的 NaBH（85%产率）和 KBH（84%产率）。这种新的合成方法基于在高压釜中使用二甲基硫代硼烷（DMS·BH）和硼氢化物（NaBH、KBH）在不同温度下在二甘醇中加热。研究发现，通过 BH、BH 和 BH 的中间形成，可以获得高纯度的 NaBH·二甘醇溶剂化物，它们都可溶于二甘醇中。在真空中加热被证明可以有效地去除配位的二甘醇，从而形成未溶剂化的 NaBH。从 KBH 直接进行高压釜合成可得到无溶剂 KBH，并且在合成之前对 KBH 进行球磨可以显著提高最终产率。这种新的合成方法为 MBH 衍生物的大规模合成铺平了道路，为更广泛的实际应用设想提供了可能。
