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The facile synthesis of the cationic dinuclear group 10 complexes [M2(PCP)2μ-Cl]+ (M = Ni, Pd, Pt) by transmetallation from a simple Ga precursor is reported (PCP = 2,6-(Ph2P)C6H3). Their use for the catalysed dehydrogenation of Me2NHBH3 shows that Ni has a higher reactivity than Pt, whereas Pd is inactive. [ABSTRACT FROM AUTHOR]

The facile synthesis of the cationic dinuclear group 10 complexes [M2(PCP)2μ-Cl]+ (M = Ni, Pd, Pt) by transmetallation from a simple Ga precursor is reported (PCP = 2,6-(Ph2P)C6H3). Their use for the catalysed dehydrogenation of Me2NHBH3 shows that Ni has a higher reactivity than Pt, whereas Pd is inactive. [ABSTRACT FROM AUTHOR]

A macrocyclic azobenzene with unique thermal stability, demonstrating potential for use in optical data storage material is presented: The Z‐isomer of this novel photoswitch exhibits unparalleled thermal stability, with a thermal half‐life surpassing 120 years at 25 °C. This stability is attributed to the strategic fluorination at two ortho‐ and both para‐positions. Comparative analyses involving its non‐fluorinated counterpart, ortho‐only‐fluorinated variant, and open‐chain analog are performed. Employing NMR and UV–vis spectroscopy, X‐ray diffraction, alongside Arrhenius, Eyring, and DFT calculations, revealed insights into its extraordinary stability. Furthermore, when incorporated into poly(methylmethacrylate), this material showcase efficient switching with visible light in the solid state, emphasizing its potential for optical data storage applications. [ABSTRACT FROM AUTHOR]

The bulky aryl thiol, MSFluindSH (1S), and aryl selenol, MSFluindSeH (1Se), possessing a tetramethyl‐s‐hydrindacen‐4'‐yl‐(Rind)‐based substituent containing two fluorenyl groups in 9 and 9'‐positions, were prepared (MSFluind=dispiro[fluorene‐9,3'‐(1',1',7',7'‐tetramethyl‐s‐hydrindacene‐4'‐yl)‐5',9"‐fluorene]). The reaction of 1S and 1Se with Et2Zn provided a monomeric zinc aryl thiolate, Zn(SMSFluind)2 (2S), and zinc aryl selenolate, Zn(SeMSFluind)2 (2Se), with essentially two‐coordinate zinc atoms. [ABSTRACT FROM AUTHOR]

The title compound, [Zn(C20H18BN2)2] (ZnL2), is an overall uncharged chelate that consists of two units of an NH-deprotonated 10-aza-9-borabenzo[h] quinoline ligand (L) per ZnII center. It was synthesized in two steps by treating the protonated ligand HL with lithium bis(trimethylsilyl)amide and further conversion with diethylzinc. Its asymmetric unit comprises one ZnL fragment; the molecule is completed by application of inversion symmetry at Zn. Due to the fourfold coordination with nitrogen atoms, the zinc(II) ion is located in a distorted tetrahedral environment. Besides the relatively short N--Zn bonds, ZnL2 is characterized by the significant protrusion of the central ion from the plane of the ligand backbone. The crystal structure is consolidated by intra- and intermolecular π-π stacking interactions, while the polarized B--N bond is barely involved in any close atom contacts. [ABSTRACT FROM AUTHOR]

The isoelectronic relationship of 1,2-azaborinine (B=N structural motif) and benzene (C=C) is well documented. Upon deprotonation of the former, the anionic 1,2-azaboratabenzene is obtained, which is isosteric with pyridine (C=N) and has a similar capability as an aromatic N-donor. We present the complexation of boron and aluminum precursors with a κ2-N,O-donating 8-hydroxy-BN-naphthalene ligand (H2(BQ), 1). Six chelate complexes with 1:1 and 2:1 stoichiometries were isolated and characterized by X-ray diffraction analysis and NMR spectroscopy. Comparing the isosteric dimethylaluminum complexes of H2(BQ) and an 8-hydroxyquinoline (HQ', 2) as a reference allowed us to quantify the influence of a formal substitution of carbon by boron on the structure and the electronic properties: While the structural parameters of the ligands were similar, the electropositive boron atom affected the electron density distributions within the complexes substantially. As the consequence, the Al–N bond was significantly shortened, and the aluminum atom showed a different coordination geometry than in the quinoline analog. Moreover, strong hypsochromic shifts of both the absorption and the emission were observed. The results highlight that the differences between CN and BN polyaromatic complexes are more distinct than between equally charged BN and CC congeners. [ABSTRACT FROM AUTHOR]

The facile synthesis of the cationic dinuclear group 10 complexes [M 2 (PCP) 2 μ -Cl] + (M = Ni, Pd, Pt) by transmetallation from a simple Ga precursor is reported (PCP = 2,6-(Ph 2 P)C 6 H 3 ). Their use for the catalysed dehydrogenation of Me 2 NHBH 3 shows that Ni has a higher reactivity than Pt, whereas Pd is inactive.

We present N -heterocycle-stabilized iodanes (NHIs) as suitable reagents for the mild oxidation of activated alcohols. Two different protocols, both involving activation by chloride additives, were used to synthesize benzylic ketones and aldehydes without overoxidation in up to 97% yield. Based on MS experiments an activated hydroxy(chloro)iodane is proposed as the reactive intermediate., (Copyright © 2024, Kuczmera et al.)

The incorporation of boron-nitrogen (BN) units into polycyclic aromatic hydrocarbons (PAHs) as an isoelectronic replacement of two carbon atoms can significantly improve their optical properties, while the geometries are mostly retained. We report the first non-π-extended penta- and hexahelicenes comprising two aromatic 1,2-azaborinine rings. Comparing them with their all-carbon analogs regarding structural, spectral and (chir)optical properties allowed us to quantify the impact of the heteroatoms. In particular, BN-hexahelicene BN[6] exhibited a crystal structure congruent with its analog CC[6], but displayed a fivefold higher fluorescence quantum yield ( φ fl = 0.17) and an outstanding luminescence dissymmetry factor (| g lum | = 1.33 × 10 -2 ). Such an unusual magnification of both properties at the same time makes BN-helicenes suitable candidates as circularly polarized luminescence emitters for applications in materials science., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

The title compound, [Zn(C 20 H 18 BN 2 ) 2 ] ( Zn L 2 ), is an overall uncharged chelate that consists of two units of an N H -deprotonated 10-aza-9-borabenzo[ h ]quinoline ligand ( L ) per Zn II center. It was synthesized in two steps by treating the protonated ligand HL with lithium bis-(tri-methyl-sil-yl)amide and further conversion with di-ethyl-zinc. Its asymmetric unit comprises one ZnL fragment; the mol-ecule is completed by application of inversion symmetry at Zn. Due to the fourfold coordination with nitro-gen atoms, the zinc(II) ion is located in a distorted tetra-hedral environment. Besides the relatively short N-Zn bonds, Zn L 2 is characterized by the significant protrusion of the central ion from the plane of the ligand backbone. The crystal structure is consolidated by intra- and inter-molecular π-π stacking inter-actions, while the polarized B-N bond is barely involved in any close atom contacts., (© Appiarius et al. 2023.)

The selective hydrogenation of the carbonyl functionality of α,β-unsaturated aldehydes and ketones is catalysed by ruthenium dichloride complexes bearing a tridentate NNS ligand as well as triphenylphosphine. The tridentate ligand backbone is flexible, as evidenced by the equilibrium observed in solution between the cis- and trans-isomers of the dichloride precatalysts, as well as crystal structures of several of these complexes. The complexes are activated by base in the presence of hydrogen and readily hydrogenate carbonyl functionalities under mild conditions. Despite the activation by base, side reactions are negligible, even for aldehyde substrates, because of the low amount of base. Thus, the corresponding allylic alcohols can be isolated in very good yields on a 10-25 mmol scale. Turnover numbers up to 200 000 were achieved., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)