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Colloidal metal nanoparticles exhibit interesting catalytic properties for the hydrogenation of (hetero)arenes. Catalysts based on precious metals, such as Ru and Rh, promote this reaction efficiently under mild reaction conditions. In contrast, heterogeneous catalysts based on earth‐abundant metals can selectively hydrogenate (hetero)arenes but require harsher reaction conditions. Bimetallic catalysts that combine precious and earth‐abundant metals are interesting materials to mitigate the drawbacks of each component. To this end, RuNi nanoparticles bearing a phosphine ligand were prepared through the decomposition of [Ru(η4‐C8H12)(η6‐C8H10)] and [Ni(η4‐C8H12)2] by H2 at 85 °C. Wide angle X‐ray scattering confirmed a bimetallic segregated structure, with Ni predominantly on the surface. Spectroscopic analyses revealed that the phosphine ligand coordinated to the surface of both metals, suggesting, as well, a partial Ni shell covering the Ru core. The RuNi‐based nanomaterials were used as catalysts in the hydrogenation of quinoline to assess the impact of the metallic composition and of the stabilizing agent on their catalytic performance. [ABSTRACT FROM AUTHOR]

Dinuclear Re(I) complexes have proportionally been much less studied than mononuclear analogues. In particular, very little information is available about their solid-state emission properties. In this work, two structural isomers of dinuclear complexes (Bi-Re-metaPhe and Bi-Re-paraPhe), which differ by the relative position of the coordination spheres on a central phenyl ring, were synthesized and compared with each other and with the parent mononuclear compound (Mono-Re-Phe), from a theoretical and experimental point of view. In solution, the electronic, electrochemical and spectroscopic properties of the dinuclear complexes were almost identical, and rather close to those of the monomer. In the solid state, the photoluminescence (PL) efficiency of dimers was not higher than that of the monomer, but a clear mechanoresponsive luminescence (MRL) effect appeared only for the former ones. The positional isomerism influenced the amplitude of this effect, as well as the aggregation-induced emission (AIE) properties in a water-acetonitrile mixture. This study reveals the importance of positional isomerism to modulate the emission properties in the solid state. It also shows the advantage of dinuclear structures to access new MRL-active materials. [ABSTRACT FROM AUTHOR]

Tetrahydro-4H-thiopyran-4-one 1-oxide 1 and sulfinyl-di-tert-butylpropionate 2 were reported as sources of bis-sulfenate anion and applied in a double pallado-catalyzed cross-coupling reaction for the synthesis of symmetrical biarylsulfoxides, tolerating a large array of electronic properties and bulkiness. The photophysical properties of a biarylsulfoxide have been explored, demonstrating an unreported TADF phenomenon on sulfoxide-containing scaffolds. [ABSTRACT FROM AUTHOR]

This study introduces bis(1‐cyanocyclohex‐1‐yl)trithiocarbonate (TTC‐bCCH) as a novel trithiocarbonate chain transfer agent and compares its reactivity with the previously described bis(2‐cyanopropan‐2‐yl)trithiocarbonate (TTC‐bCP) for the reversible addition‐fragmentation chain transfer (RAFT) polymerization of styrene (St), n‐butyl acrylate (nBA), and methyl methacrylate (MMA). Significant findings include the effective control of Mn and low dispersities from the onset of polymerization of St and nBA showing swift addition‐fragmentation kinetics, leading to similar behaviors between the two RAFT agents. In contrast, a fourfold decrease of the chain transfer constant to MMA is established for TTC‐bCCH over TTC‐bCP. This trend is confirmed through density functional theory (DFT) calculations. Finally, the study compares thermoplastic elastomer properties of all‐(meth)acrylic ABA block copolymers produced with both RAFT agents. The impact of dispersity of PMMA blocks on thermomechanical properties evaluated via rheological analysis reveals a more pronounced temperature dependence of the storage modulus (G′) for the triblock copolymer synthesized with TTC‐bCCH, indicating potential alteration of the phase separation. [ABSTRACT FROM AUTHOR]

Pentafluorophenyl copper(I)–biarylsulfoxide complexes, existing as [Cu(C6F5)]4L2, both in solution and in the solid state, were prepared and thoroughly characterized. Subsequently, the photochemistry of the complexes was explored, showing inherent photoreactivity of the biarylsulfoxide moiety within the coordination sphere of the copper. Photoinduced cross-coupling reactions between the anthryl moiety of bis-anthracenylsulfoxide and pentafluorobenzene, and synthesis of Cu2O (cuprite), were demonstrated. [ABSTRACT FROM AUTHOR]

A ruthenium nitrosyl complex of formula [RuII(fluorene(C6)CH2O-terpy)(bipy)(NO)]3+ (AC) in which fluorene(C6) is the 9,9-dihexylfluorene, terpy the 2,2′;6′,2′′-terpyridine, and bipy the 2,2′-bipyridine is presented with its related [RuII(MeO-terpy)(bipy)(NO)]3+ (C) and 9,9-dihexylfluorene 2-hydroxymethylfluorene (A) building blocks. The reference complex C undergoes NO release capabilities under irradiation at λ = 365 nm. The effect of the introduction of the fluorescent A antenna within the resulting AC complex is discussed both experimentally and theoretically. The importance of the encaging parameter defined as φAC·IAC, in which IAC is the quantity of light absorbed by AC and φAC the quantum yield of NO release is evidenced and found to be concentration dependent. The conditions of optimization of the antenna approach to maximize φAC·IAC are discussed. The crystal structure of [RuII(fluorene(C6)CH2O-terpy)(bipy)(NO2)](PF6), the last intermediate in the synthesis of AC is also presented. [ABSTRACT FROM AUTHOR]

Several ortho‐carboranes bearing a phenoxy or a phenylamino group in the B9 position were prepared employing various protection and deprotection strategies. Following established protocols, dendritic compounds were synthesized from a hexachlorocyclotriphosphazene or thiophosphoryl chloride core, and possible anchoring options for the B9‐substituted ortho‐carboranes were investigated experimentally and theoretically (DFT). Furthermore, 1‐ or 1,2‐phosphanyl‐substituted carborane derivatives were obtained. The resulting diethyl‐, diisopropyl‐, di‐tert‐butyl‐, diphenyl‐ or diethoxyphosphines bearing a tunable ortho‐carborane moiety are intriguing ligands for future applications in homogeneous catalysis or the medicinal sector. [ABSTRACT FROM AUTHOR]