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The cobalt bis(dicarbollide)(1−) anion (1−), [(1,2-C2B9H11)2-3,3′-Co(III)](1−), plays an increasingly important role in material science and medicine due to its high chemical stability, 3D shape, aromaticity, diamagnetic character, ability to penetrate cells, and low cytotoxicity. A key factor enabling the incorporation of this ion into larger organic molecules, biomolecules, and materials, as well as its capacity for "tuning" interactions with therapeutic targets, is the availability of synthetic routes that enable easy modifications with a wide selection of functional groups. Regarding the modification of the dicarbollide cage, syntheses leading to substitutions on boron atoms are better established. These methods primarily involve ring cleavage of the ether rings in species containing an oxonium oxygen atom connected to the B(8) site. These pathways are accessible with a broad range of nucleophiles. In contrast, the chemistry on carbon vertices has remained less elaborated over the previous decades due to a lack of reliable methods that permit direct and straightforward cage modifications. In this review, we present a survey of methods based on metalation reactions on the acidic C-H vertices, followed by reactions with electrophiles, which have gained importance in only the last decade. These methods now represent the primary trends in the modifications of cage carbon atoms. We discuss the scope of currently available approaches, along with the stereochemistry of reactions, chirality of some products, available types of functional groups, and their applications in designing unconventional drugs. This content is complemented with a report of the progress in physicochemical and biological studies on the parent cobalt bis(dicarbollide) ion and also includes an overview of recent syntheses and emerging applications of boron-substituted compounds. [ABSTRACT FROM AUTHOR]

The action of AlCl3 on room-temperature tetrachloromethane solutions of anti-B18H22 (1) results in a mixture of fluorescent isomers, 3,3′-Cl2-B18H20 (2) and 3,4′-Cl2-B18H20 (3), together isolated in a 76% yield. Compounds 2 and 3 are capable of the stable emission of blue light under UV-excitation. In addition, small amounts of other dichlorinated isomers, 4,4′-Cl2-B18H20 (4), 3,1′-Cl2-B18H20 (5), and 7,3′-Cl2-B18H20 (6) were isolated, along with blue-fluorescent monochlorinated derivatives, 3-Cl-B18H21 (7) and 4-Cl-B18H21 (8), and trichlorinated species 3,4,3′-Cl3-B18H19 (9) and 3,4,4′-Cl3-B18H19 (10). The molecular structures of these new chlorinated derivatives of octadecaborane are delineated, and the photophysics of some of these species are discussed in the context of the influence that chlorination bears on the luminescence of anti-B18H22. In particular, this study produces important information on the effect that the cluster position of these substitutions has on luminescence quantum yields and excited-state lifetimes. [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]

The interaction of aminomethylphosphonic acid (H2amp) with the Zn(ii)–cyclen complex and the formation of ternary complexes was studied by potentiometry and 31P NMR titrations. Data evaluation of each of the methods separately was found to be insufficient. Thus, data obtained from the both methods were simultaneously treated with the computer program OPIUM. The determined stability constants indicated only weak (log K∼ 3) coordination of aminomethylphosphonic acid through the phosphonate group. The chelating coordination mode with the participation of the amine group was not confirmed. In excess of Zn(ii)–cyclen, the formation of dinuclear complexes, in which two Zn(ii)–cyclen units are bridged by a phosphonate group, was observed and their presence was confirmed by mass spectrometry. Such a coordination motif is typical for phosphonates in the solid state and also for phosphatases. [ABSTRACT FROM AUTHOR]

Luminescence is observed in three novel macropolyhedral nineteen- and eighteen-vertex chalcogenaboranes: Se 2 B 17 H 17 (1), SeB 17 H 19 (3) and SeB 18 H 20 (4). This led us to the recognition that previously published macropolyhedral heteroborane species might also exhibit luminescence. Thus, the known nineteen- and eighteen-vertex dithiaboranes S 2 B 17 H 17 (2), n-S 2 B 16 H 16 (5) and i-S 2 B 16 H 16 (6) were synthesised and also found to exhibit a range of luminescent properties. These macropolyhedral species are very different from the previously unique fluorescent binary borane B 18 H 22 in terms of their structural architectures, by the presence of borane cluster hetero atoms, and, as in the cases of 5 and 6, that their synthetic origins are not derived simply through the modification of B 18 H 22 itself. They consequently greatly expand the possibilities of finding new luminescent inorganic borane species., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)