An atom-economical method for the direct B À H functionalization of nido-carboranes (7,8-nido-C 2 B 9 H 12 À)h as been developed under electrochemical reaction conditions.I n this reaction system, anodic oxidation serves as ag reen alternative for traditional chemical oxidants in the oxidation of nido-carboranes.N ot ransition-metal catalyst is required and different heteroatoms bearing al one pair are reactive in this transformation. Coupling nido-carboranes with thioethers, selenides,t ellurides,N-heterocycles,p hosphates,p hosphines, arsenides and antimonides demonstrates high site-selectivity and efficiency.I mportantly,n ido-carboranes can be easily incorporated into drug motifs through this reaction protocol.

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The efficient and selective functionalization of icosahedral carboranes (C 2 B 10 H 12 ) at the boron vertexes is a long-standing challenge owing to the presence of 10 inert B−H bonds in a similar chemical environment. Herein, we report a new reaction paradigm for direct B−H functionalization of icosahedral carboranes via B−H homolysis enabled by a nitrogen-centered radical-mediated hydrogen atom transfer (HAT) strategy. Both the HAT process of the carborane B−H bond and the resulting boroncentered carboranyl radical intermediate have been confirmed experimentally. The reaction occurs at the most electron-rich boron vertex with the lowest B−H bond dissociation energy (BDE). Using this strategy, diverse carborane derivatization, including thiolation, selenation, alkynylation, alkenylation, cyanation, and halogenation, have been achieved in satisfactory yields under a photoinitiated condition in a metal-free and redox-neutral fashion. Moreover, the synthetic utility of the current protocol was also demonstrated by both the scale-up reaction and the construction of carborane-based functional molecules. Therefore, this methodology opens a radical pathway to carborane functionalization, which is distinct from the B−H heterolytic mechanism in the traditional strategies.

Functionalization of carboranes in a vertex‐specific manner is a perennial challenge. Here, we report a photocatalytic B−C coupling for the selective functionalization of carboranes at the boron site which is most distal to carbon. This reaction was achieved by the photo‐induced decarboxylation of carborane carboxylic acids to generate boron vertex‐centered carboranyl radicals. Theoretical calculations also demonstrate that the reaction more easily occurs at the boron site bearing higher electron density owing to the lower energy barrier for a single‐electron transfer to generate a carboranyl radical. By using this strategy, a number of functionalized carboranes could be accessed through alkylation, alkenylation, and heteroarylation under mild conditions. Moreover, both a highly efficient blue emitter with a solid‐state luminous efficiency of 42 % and a drug candidate for boron neutron capture therapy (BNCT) containing targeting and fluorine units were obtained.

Performance of tunable emissions in aggregates is highly desirable but challenging owing to the restricted molecular conformations for luminogens. Herein, we designed and synthesized a new “flexible” luminogen, a carborane-cored...