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Polyhedral boranes are a class of well-known boron molecular clusters with unique physical and chemical properties, and great efforts have been made in the past decades to find more effective synthetic methods. However, the established synthetic methods suffer from low efficiency and low selectivity because the mechanism of the B–H bond condensation reaction, critical for the synthesis of the polyhedral boranes, is not well understood. Here we report highly selective and efficient synthetic methods of the salts of the tetradecahydridoundecaborate (1–) (B11H14−) and dodecahydrido-dodecaborates (2–) (B12H122−) anions by employing commercially available and inexpensive starting materials. Both theoretical and experimental investigations are carried out to elucidate the reaction mechanisms. We have found that the nature of the B–H bond condensation is the dihydrogen bonding interaction in which the positively charged hydrogens (bridged hydrogens) play a crucial role. The current study has not only led to more effective and selective synthetic methods for B11H14− and B12H122− but also unveiled the nature of the B–H bond condensation and the general formation mechanisms of polyhedral boranes. This finding will facilitate the development of more effective synthetic methods for polyhedral boranes and spur their wide application. [ABSTRACT FROM AUTHOR]

An efficient method for the synthesis of M2B10H14 (M = Na and K) has been developed. The two possible formation mechanisms of the B10H142− anion are proposed, in which the NH2BH3− anion acts as a proton abstractor and a hydride donor. Furthermore, the B10H13− and B10H15− intermediates were detected. [ABSTRACT FROM AUTHOR]

All-solid-state K batteries are ideal energy storage devices for grid-scale applications of renewable energies. A novel electrolyte K[B3H7NH2BH2NH2B3H7] with weakly coordinating anions was synthesized. It has a high K+ conductivity of 1.01 × 10−4 S cm−1 at 75 °C, which is probably due to the increased electrostatic potential and size of the anions. [ABSTRACT FROM AUTHOR]

A safe and efficient synthetic method for MB3H8 (M = Na, K, Rb and Cs) has been developed with excellent yields by directly reacting the corresponding MBH4 with the dimethyl sulfide borane complex (DMS·BH3). A general mechanism for constructing B3H8−, a basic unit for building polyhedral boranes, has been unravelled. [ABSTRACT FROM AUTHOR]

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]

There exists an interplay between borane and a Lewis base in their adducts. However, studies on these adducts so far have mainly focused on the different reactions of B-H bonds with limited attention given to the influence of borane on the chemistry of the Lewis base, except for BF 3 and BAr 3 . Herein, we have synthesized novel borane adducts with pyridine derivatives, Py·B 3 H 7 , in which the coordination of B 3 H 7 efficiently achieved the intra-molecular charge transfer. The strong B-N bond in these adducts resulted in the formation of stable dearomatic intermediates of pyridine derivatives, confirmed by 1 H and 11 B NMR spectroscopy, from which different reactions have transpired to realize C(sp 3 )-H and C(sp 2 )-H functionalization under mild conditions. The B 3 H 7 pyridine derivatives are stable and do not dissociate or decompose during the reaction process. The high stability of the B-N bond makes this method a good option for boron-containing drugs with potential for use in boron neutron capture therapy (BNCT)., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

MN1 C-terminal truncation (MCTT) syndrome was first reported in 2020 and only 28 patients have been recorded to date. Since MCTT syndrome is a newly defined and rare syndrome with many clinical features, the present study reviewed the manifestations and management of oral and dental anomalies. Gene variants of MCTT syndrome and their positive phenotypes were summarised. The phenotypes of variants in two exons differed from each other mainly in the craniomaxillofacial region, including brain MRI abnormalities and palatal morphology. Pathogenic mechanisms, especially in craniofacial and oral anomalies, were discussed. Appropriate treatments in the stomatology and respiratory departments could improve the symptoms of MCTT syndrome. The different sites of MN1 gene variants may influence the clinical symptoms and there may be racial differences in MCTT syndrome. We recommend oral and pulmonary evaluations for the multidisciplinary treatment of MCTT syndrome.

An efficient method for the synthesis of M 2 B 10 H 14 (M = Na and K) has been developed. The two possible formation mechanisms of the B 10 H 14 2- anion are proposed, in which the NH 2 BH 3 - anion acts as a proton abstractor and a hydride donor. Furthermore, the B 10 H 13 - and B 10 H 15 - intermediates were detected.

The design, synthesis, and applications of new boranes are eternal topics in boron chemistry. A new bis(borane)alkanethiolate salt, K[BH 3 S(CH 3 )BH 3 ], was synthesized in high yield by the reaction of K with (CH 3 ) 2 S·BH 3 at room temperature. The formation mechanism was elucidated based on experimental and theoretical studies. The single-crystal structure of the K[BH 3 S(CH 3 )BH 3 ]·18-crown-6 adduct was determined in which the B-S-B bonding information of K[BH 3 S(CH 3 )BH 3 ] was illustrated for the first time. Using K[BH 3 S(CH 3 )BH 3 ] as a starting material, KB 3 H 8 was successfully synthesized.

All-solid-state potassium batteries are promising candidates in the fields of large-scale energy storage owing to their intrinsic safety, stability, and cost-effectiveness. However, a suitable solid-state electrolyte with high ionic conductivity and favorable interfacial stability is a major challenge for the design and development of these batteries. Herein, we report the synthesis of new KB 3 H 8 · n NH 3 B 3 H 7 ( n = 0.5 and 1) complexes to develop suitable solid-state K-ion conductors for batteries. Both the complexes undergo a reversible phase transition below the thermal decomposition temperature. The optimal KB 3 H 8 ·NH 3 B 3 H 7 delivers a solid-state K-ion conductivity of 1.3 × 10 -4 S cm -1 at 55 °C with an activation energy of 0.44 eV after a transition from a monoclinic to an orthorhombic phase, which is the highest value of K borohydrides reported to date and places KB 3 H 8 ·NH 3 B 3 H 7 among the leading solid-state K-ion conductors. Moreover, KB 3 H 8 ·NH 3 B 3 H 7 reveals a K-ion transference number of nearly 0.93, an electrochemical stability window of 1.2 to 3.5 V vs K + /K, a good capability of K dendrite suppression, and a remarkable stability against the K metal anode due to the formation of the stable interface. These performances make KB 3 H 8 ·NH 3 B 3 H 7 a promising electrolyte for all-solid-state potassium batteries.

All-solid-state K batteries are ideal energy storage devices for grid-scale applications of renewable energies. A novel electrolyte K[B 3 H 7 NH 2 BH 2 NH 2 B 3 H 7 ] with weakly coordinating anions was synthesized. It has a high K + conductivity of 1.01 × 10 -4 S cm -1 at 75 °C, which is probably due to the increased electrostatic potential and size of the anions.

Improved methods for the synthesis of KB 3 H 8 , NH 3 B 3 H 7 , and N -alkyl analogues of NH 3 B 3 H 7 have been developed based on previous works. KB 3 H 8 was synthesized by the reaction of metallic potassium (K) with borane dimethyl sulfide ((CH 3 ) 2 S·BH 3 ) with high yield and atom-economy. In the preparation of NH 3 B 3 H 7 and its N -alkyl analogues, KB 3 H 8 served as a starting material and was converted to THF·B 3 H 7 first through reactions with HCl diethyl ether solution or oxidation agent CoCl 2 . Then, the formed THF·B 3 H 7 in situ reacted with the corresponding ammonia or amines to form the amine borane final products. This work paves an alternative way for preparing organic-inorganic hybrid materials containing B, N, and C atoms.

A safe and efficient synthetic method for MB 3 H 8 (M = Na, K, Rb and Cs) has been developed with excellent yields by directly reacting the corresponding MBH 4 with the dimethyl sulfide borane complex (DMS·BH 3 ). A general mechanism for constructing B 3 H 8 - , a basic unit for building polyhedral boranes, has been unravelled.