Search

Tris(3,5‐dimethylpyrazolyl)borate aluminum dihalides TpMe2AlX2 (X=Cl, Br and I) can be potential precursors for preparing highly electrophilic dications as well as low oxidation state aluminum compounds. However, the coordinative unsaturation in TpMe2AlX2 makes them susceptible to rearrangement to [Tp2Al][AlX4]. In this work, we revisited the synthesis of TpMe2AlX2 by isolating the solvent‐stabilized tris(3,5‐dimethylpyrazolyl)borate aluminum dihalides TpMe2AlX2(L) (X=Cl, Br; L=THF, HPMA). Efforts to isolate TpMe2All2 resulted in the ring opening of THF revealing the mediation of a highly reactive cationic aluminum species. The monocationic, [TpMe2AlCl(THF)2][B{C6H3(CF3)2}4] was prepared from TpMe2AlCl2(THF) via silver salt metathesis. Attempts to prepare the dicationic species [TpMe2Al(THF)3]2+ resulted in the instantaneous ring‐opening polymerization of THF. [ABSTRACT FROM AUTHOR]

The first carbazole-embedded p-benziporphyrinoid is synthesized by a [3+1] acid-catalyzed condensation between appropriate coupling partners. The macrocycle 1 exhibited orange emission and showed a large Stokes shift of 5831 cm−1. Intriguingly, it shows a selective affinity towards Hg2+ ions over other metal-ions in a reversible manner. Job's plot confirmed the 1 : 1 stoichiometry with unambiguous confirmation of both 1 and 1-Hg by single crystal X-ray analysis. [ABSTRACT FROM AUTHOR]

We present the reactivity of the Mg–C and the β-CH bonds in the trigonal pyramidal [(pmdta)Mg(nBu)]+ exhibiting a weak Mg⋯F interaction with counter anion, [B(C6F5)4]−. Instantaneous β-hydride reactivity with benzophenone, reductive alkylation of phenyl benzoate, and straightforward synthesis of [(pmdta)MgH]+via metathesis with pinacolborane/phenylsilane are discussed. [ABSTRACT FROM AUTHOR]

The solid tumor microenvironment (TME) imprints a compromised metabolic state in tumor-infiltrating T cells (TILs), hallmarked by the inability to maintain effective energy synthesis for antitumor function and survival. T cells in the TME must catabolize lipids via mitochondrial fatty acid oxidation (FAO) to supply energy in nutrient stress, and it is established that T cells enriched in FAO are adept at cancer control. However, endogenous TILs and unmodified cellular therapy products fail to sustain bioenergetics in tumors. We reveal that the solid TME imposes perpetual acetyl-coenzyme A (CoA) carboxylase (ACC) activity, invoking lipid biogenesis and storage in TILs that opposes FAO. Using metabolic, lipidomic, and confocal imaging strategies, we find that restricting ACC rewires T cell metabolism, enabling energy maintenance in TME stress. Limiting ACC activity potentiates a gene and phenotypic program indicative of T cell longevity, engendering T cells with increased survival and polyfunctionality, which sustains cancer control. [Display omitted] • The tumor microenvironment induces lipid droplet (LD) accumulation in dysfunctional CD8+ TILs • Acetyl-CoA carboxylase (ACC) directs LD accumulation in CD8+ T cells • Inhibition of ACC in CD8+ T cells facilitates fatty acid oxidation • Restraining ACC promotes CD8+ TIL persistence and tumor control Hunt and Hurst et al. report that the TME engages ACC in CD8+ TILs, culminating in profound steatosis visible by accumulation of lipid droplets. Limiting ACC ablates fatty acid synthesis and storage in CD8+ T cells, enforcing mitochondria free fatty acid utilization to sustain bioenergetics that enable prolonged antitumor immunity. [ABSTRACT FROM AUTHOR]

A systematic approach to obtain bromobismuthates with various bismuth/halide ratios stabilised by 2,6-diisopropylanilinium cations [ArNH3] (Ar = 2,6-diisopropylphenyl) is presented. New bromobismuthate compounds [(ArNH3)(BiBr4)]∞ (1), [(ArNH3)3(Bi2Br9)]∞ (2), [(ArNH3)3(BiBr6)] (3) and [(ArNH3)4(BiBr6)(Br)] (4) with Bi/Br ratios of 1:4, 1:4.5, 1:6 and 1:7 have been isolated and structurally characterised. [Bi2Br9]∞ is a new structural motif in halobismuthate chemistry. In all the compounds, extensive hydrogen bonding is observed between the bromobismuthate moiety and the 2,6-diiosopropylanilinium cation, thus stabilising the inorganic–organic hybrid structures. Preliminary optical spectroscopic studies indicate that the optical band gap can be tuned by controlling the bismuth/halide ratio, which results in different dimensionalities in the halobismuthate structure. The compounds exhibit thermal stability up to 250 °C. [ABSTRACT FROM AUTHOR]

Zinc has been an element of choice for carbon dioxide reduction in recent years. Zinc compounds have been showcased as catalysts for carbon dioxide hydrosilylation and hydroboration. The extent of carbon dioxide reduction can depend on various factors, including electrophilicity at the zinc center and the denticity of the ancillary ligands. In a few cases, the addition of Lewis acids to zinc hydride catalysts markedly influences carbon dioxide reduction. These factors have been investigated by exploring elementary reactions of carbon dioxide hydrosilylation and hydroboration by using cationic zinc hydrides bearing tetradentate tris[2-(dimethylamino)ethyl]amine and tridentate N,N,N',N'',N''-pentamethyldiethylenetriamine in the presence of triphenylborane and tris(pentafluorophenyl)borane., (© 2021 Wiley-VCH GmbH.)