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Carbon substituted cobalt bis(dicarbollide) alkyl halides [(1-X-(CH2)n-1,2-C2B9H10)(1,2-C2B9H11)-3,3′-Co]Me4N (X = Br, I; n = 1–3) are prepared in high yields (>90%) from their corresponding alcohols without side skeletal substitutions. These species offer access to the synthesis of aromatic cobalt bis(dicarbollide) amines, however only for particular terminal halogen substitution, the propylene pendant arm, and under appropriately controlled reaction conditions. Thus, the compounds substituted at cage carbon atoms with a propylene linker and terminal aromatic amine groups could be prepared. In other cases, numerous irregular reaction pathways occur, undoubtedly as a consequence of the bulky anionic boron cage in close proximity to the reaction site. Among them, an unusual intramolecular hydroboration forming rigidified carbon-to-boron bridged isomeric anions with an asymmetric structure that correspond to formulae [(1,8′-μ-C2H4)-(1,2-C2B9H10)(1′,2′-C2B9H10)-3,3′-Co]− and [(1,7′-μ-C2H4)-(1,2-C2B9H10)(1′,2′-C2B9H10)-3,3′-Co]− is described herein and the former isomer is structurally characterized. This product with a restrained geometry is widely accessible through nucleophile and/or thermally induced decomposition of (pseudo)halides attached to the cage via an ethylene linker. Surprisingly enough, also doubly bridged isomeric species [(1,8-μ-C2H4-1,2-C2B9H9)2-3,3′-Co]− and [(1,7-μ-C2H4-1,2-C2B9H9)2-3,3′-Co]− are available in good yield using these methods. Furthermore, other more typical side reactions are discussed, i.e. nucleophilic reactions of propyl halides with Me3N formed apparently by disproportionation of Me4N+ at higher temperatures or with pyridine used as a base. [ABSTRACT FROM AUTHOR]

Derivatives of the nido‐7,8‐C2B9H12(1‐) (dicarbollide ion) and [3,3′‐Co‐(1,2‐C2B9H11)2](1‐) cobalt sandwich (COSAN) ion represent groups of extremely chemically and thermally stable abiotic compounds. They are being investigated in many research areas, that is, medicinal chemistry, material sciences, analytical chemistry, and electrochemistry. The chirality of these compounds remains still grossly overlooked, what is also reflected in limited number of reports on their chiral separations. Continued progress depends on reliable, fast, and cost‐effective methods for such separations. Recently, chiral separations of COSAN derivatives were achieved in liquid chromatography and supercritical fluid chromatography. Only five anionic derivatives of nido‐7,8‐C2B9H12(1‐) were successfully enantioseparated in liquid chromatography. Efforts to separate anionic nido‐7,8‐C2B9H12(1‐) in supercritical chromatography have failed, and only a few dicarbollide ions were separated using liquid chromatography. Generally, all chiral separations in liquid chromatography took about 30 min. Herein, we identify a versatile column capable of separating both COSAN and nido‐7,8‐C2B9H12(1‐) derivatives and achieve faster analyses times employing commercially available superficially porous chiral stationary phases. The semisynthetic hydroxypropyl β‐cyclodextrin‐based column (CDShell‐RSP) is identified as the column of choice from the tested columns by separating 19 of 27 compounds from each structural motifs tested mainly in less than 10 min. The dihydroxyalkyl, oxygen‐bridged hydroxyalkyl, and bisphenylene‐bridged COSAN derivatives were baseline separated in less than 5 min exceeding the results of supercritical fluid chromatography. Methods developed herein will aid synthetic chemists without the possession of a supercritical fluid chromatograph to achieve fast chiral separations of COSAN and derivatives of nido‐7,8‐C2B9H12(1‐) on a common liquid chromatograph without the need of dedicated instrumentation. [ABSTRACT FROM AUTHOR]

Correction for 'Synthetic routes to carbon substituted cobalt bis(dicarbollide) alkyl halides and aromatic amines along with closely related irregular pathways' by Jan Nekvinda et al., Dalton Trans., 2024, 53, 5816–5826, https://doi.org/10.1039/D4DT00072B. [ABSTRACT FROM AUTHOR]

This article discusses the study of superchaotropic boron clusters and their ability to transport hydrophilic cargos across lipid membranes and inside cells. The researchers found that the size and polarizability of the clusters are more important than their chemical composition in determining their carrier potential and toxicity. The article also mentions other research articles on topics such as aggregation-induced emission, ferroelectrics, and nanocarbons. [Extracted from the article]

This article, published in Angewandte Chemie, discusses the study of superchaotropic boron clusters and their ability to transport hydrophilic cargos across lipid membranes and inside cells. The researchers found that the size and polarizability of the clusters are more important than their chemical composition in determining their carrier potential and toxicity. The article also includes research on responsive organic fluorescent aggregates, lead halide luminescent ferroelectrics, and the synthesis of a longitudinally helical molecular carbon. [Extracted from the article]