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This study proposes an innovative strategy to enhance the pharmacophore model of antimicrobial bismuth thiolato complex drugs by substituting hydrocarbon ligand structures with boron clusters, particularly icosahedral closo‐dicarbadodecaborane (C2B10H12, carboranes). The hetero‐ and homoleptic mercaptocarborane complexes BiPh2L (1) and BiL3 (2) (L=9‐S‐1,2‐C2B10H11) were prepared from 9‐mercaptocarborane (HL) and triphenylbismuth. Comprehensive characterization using NMR, IR, MS, and XRD techniques confirmed their successful synthesis. Evaluation of antimicrobial activity in a liquid broth microdilution assay demonstrated micromolar to submicromolar minimum inhibitory concentrations (MIC) suggesting high effectiveness against S. aureus and limited efficacy against E. coli. This study highlights the potential of boron‐containing bismuth complexes as promising antimicrobial agents, especially targeting Gram‐positive bacteria, thus contributing to the advancement of novel therapeutic approaches. [ABSTRACT FROM AUTHOR]

Herein we report an unprecedented, convenient NHC‐catalyzed one‐pot cascade reaction to afford α,ω‐difunctionalized hydroxytrifluoromethyl alkynones and allenones in a single step. The critical fragile aliphatic aldehydes are introduced by a base‐mediated in situ Grob‐type fragmentation of their corresponding latent cyclic vinylogous hemiacetal triflate (VHAT) and γ‐hydroxy vinyl triflate (GHVT) precursors, avoiding typical problems and losses upon isolation. The ′demasked′ aldehydes are subsequently trapped by NHC‐catalyzed umpolung and further metal‐free C−C‐cross‐coupling to access a broad scope of terminally modified alkynyl or allenyl aliphatic, aromatic and heteroaromatic trifluoromethyl ketones as multifunctionalized, high‐value building blocks for advanced synthetic applications. Additional synthetic utility of this approach is demonstrated with the possibility for asymmetric variants using chiral NHC‐catalysts. [ABSTRACT FROM AUTHOR]

Modern catalysis takes advantage of aryl-based interactions to tune and control reactions. In the design of N-heterocyclic-carbene catalysts, both the electronic and steric nature of the nitrogen substituents play a crucial role. Although hydrocarbon-based systems and especially aryl residues have contributed considerably to overcome multifaceted catalytic challenges, the unique properties of carborane moieties, including delocalized charge, potential planar chirality, and well-known thermodynamic stability, offer unprecedented opportunities to develop new catalysts while being employed as aryl mimetics. We report a straightforward synthetic route to a novel zwitterionic triazolium-based N-heterocyclic carbene (NHC) precatalyst bearing a 7,8-dicarba- nido-undecaboranyl substituent. The catalyst's excellent activity and its broad applicability are demonstrated in a wide range of organocatalytic transformations. Comparison of the performance with known N-aryl NHC catalysts offers preliminary insights into the stereoelectronic nature of this nido-carboranyl substituent. [ABSTRACT FROM AUTHOR]

The mountain ash (rowan tree) belongs to the adaptable trees of pioneer vegetation. Its fruits are edible and can be used for dishes and beverages. Appropriate knowledge is, however, required to avoid dissapointments. Their use in folk medicine is also known. In the German Ore Mountain region there is a special folk song as a song of praise for the tree. Typical chemical ingredients are the constituents parasorboside ( 1), a glucoside, parasorbinic acid ( 2), a lactone, and sorbinic acid ( 3), an unsaturated carboxylic acid. It is chemically accessible from 2 and used as a preservative. In more than 100 years, the structures were determined by renowned chemists. The access to 1, 2, and 3 based on the mountain-ash rowan berries is described. All analytical spectra were recorded and are reproduced and interpreted either in the main part or in the supporting information. [ABSTRACT FROM AUTHOR]

Invited for the cover of this issue are the groups of Kirsten Zeitler and Evamarie Hey-Hawkins at the University of Leipzig. The image depicts the carborane catalyst being a result of a long hatching process that eventually provides the starting point of a new member of the NHC-catalyst family. Read the full text of the article at . [ABSTRACT FROM AUTHOR]

A new offspring of the organocatalyst family has hatched from the merger of covalent catalysis and a carborane as an aryl‐mimetic replacement: the novel zwitterionic triazolium based N‐heterocyclic carbene (NHC) precatalyst bears a 7,8‐dicarba‐nido‐undecaboranyl substituent (nidus (lat.)=nest) and offers excellent activity and broad applicability in a wide range of organocatalytic transformations. The straightforward synthesis and a detailed comparison to recent aryl‐based precatalysts provides useful insights to pave the way for further development of this unprecedented class of catalysts. More information can be found in the Full Paper by K. Zeitler et al. on page 7932. [ABSTRACT FROM AUTHOR]