Unraveling the Mechanism of Hydrogen Atom Transfer by a Nickel-Hypochlorite Species and the Influence of Electronic Effects.

The oxidation of hydrocarbons is an important chemical transformation with relevance to biology and industry. Ni-catalyzed transformations are more scarce compared to Mn or Fe but have gained attention in recent years, affording efficient oxidations. Understanding the mechanism of action of these catalysts, including the detection and characterization of the active nickel-oxygen species, is of interest to design better catalysts.

The Hydronaphthalide Monoanion: Isolation of the "red transient" Birch Intermediate from liquid Ammonia.

Birch reactions employing alkali metals in ammonia have been a well-established method for the reduction and functionalisation of aromatic compounds for nearly 100 years. Speculations regarding intermediates in the reaction pathway have been discussed since the beginning. We hereby report the isolation of NMe(HNaph) (1), a kinetically trapped intermediate of the Birch reaction of naphthalene and sodium in liquid ammonia.

Fluorinated Dialkyl Chloronium Salts: Synthesis and Reactivity for Fluoroalkylation and Hydride Abstraction.

A new concept for the synthesis of dialkyl chloronium cations [R-Cl-R] is described (R=CH, CHCF), that allows the formation of fluorinated derivatives. By utilizing the xenonium salt [XeOTeF][M(OTeF)] (M=Sb, n=6; M=Al, n=4) chlorine atoms of chloroalkanes or the deactivated chlorofluoroalkane CHClCF are oxidized and removed as ClOTeF leading to the isolation of the corresponding chloronium salt. Since the resulting highly electrophilic cation [Cl(CHCF)] is able to alkylate weak nucleophiles, this compound can be utilized for the introduction of a fluorinated alkyl group to those.

Silylene-Stabilized Neutral Dibora-Aromatics with a B═B Bond.

The unprecedented silylene-supported dibenzodiboraoxepin and 9,10-diboraphenanthrene complexes and were synthesized. The (NHSi)B(xanthene) [NHSi = PhC(NtBu)(MeN)Si:] results from debromination of the bis(NHSi)-stabilized bis(dibromoboryl)xanthene with potassium graphite (KC); is capable of activating white phosphorus and ammonia to form the BP cage compound and HN-B-B-H diborane species , respectively. The thermal rearrangement of affords the 9,10-dihydro-9,10-diboraphenanthrene through a bis(NHSi)-assisted intramolecular reductive C-O-C deoxygenation process.

Decoupling of rotation and translation at the colloidal glass transition.

In dense particle systems, the coupling of rotation and translation motion becomes intricate. Here, we report the results of confocal fluorescence microscopy where simultaneous recording of translational and rotational particle trajectories from a bidisperse colloidal dispersion is achieved by spiking the samples with rotational probe particles. The latter consist of colloidal particles containing two fluorescently labeled cores suited for tracking the particle's orientation.

Adamantane-type clusters: compounds with a ubiquitous architecture but a wide variety of compositions and unexpected materials properties.

The research into adamantane-type compounds has gained momentum in recent years, yielding remarkable new applications for this class of materials. In particular, organic adamantane derivatives (AdR) or inorganic adamantane-type compounds of the general formula [(RT)E] (R: organic substituent; T: group 14 atom C, Si, Ge, Sn; E: chalcogenide atom S, Se, Te, or CH) were shown to exhibit strong nonlinear optical (NLO) properties, either second-harmonic generation (SHG) or an unprecedented type of highly-directed white-light generation (WLG) - depending on their respective crystalline or amorphous nature. The (missing) crystallinity, as well as the maximum wavelengths of the optical transitions, are controlled by the clusters' elemental composition and by the nature of the organic groups R.

Correction: Deciphering the chemical bonding of the trivalent oxygen atom in oxygen doped graphene.

[This corrects the article DOI: 10.1039/D4SC00142G.].

Total Synthesis of (15R)- and (15S)-Prostaglandin A.

From both pharmaceutical and structural perspectives, the large family of prostaglandins represent a truly remarkable class of natural products. Prostaglandin A is a tissue hormone naturally found in human seminal plasma and in the sea whip Plexaura homomalla with yet poorly understood biological or therapeutic effects. Herein, a novel strategy for the stereoselective construction of both naturally occurring prostaglandin A epimers and first insights into their functional effects on the major inhibitory neurotransmitter γ-aminobutyric acid (GABA) type A receptors (GABAR) are provided.

Identification and structural elucidation of an oxidation product generated during stability studies of Cabergoline drug product.

Cabergoline is a dopamine agonist with applications as anti-Parkinson drug and prolactin inhibitor. The cabergoline drug product Laktostop® 50 µg/mL is used in veterinary medicine for lactation suppression in cats and dogs e.g.

Optical and Electrical Properties of A[VS] (A = Na, K) Synthesized via a Straightforward and Scalable Solid-State Method.

Two literature-known sulfido vanadates, Na[VS] and K[VS], were obtained through a straightforward and scalable synthetic method. Highly crystalline powders of both compounds were obtained from the homogeneous molten phases of starting materials via a─comparably rapid─solid-state technique. Low-temperature structure determination, ambient temperature powder diffraction, and solid-state NMR spectroscopy verify previous structural reports and indicate purity of the obtained samples.

Formation, Structure and Reactivity of a Beryllium(0) Complex with Mg-Be Bond Polarization.

Attempts to create a novel Mg-Be bond by reaction of [(BDI*)MgNa] with Be[N(SiMe)] failed; BDI*=HC[(tBu)C=N(DIPeP)], DIPeP=2,6-EtC-phenyl. Even at elevated temperatures, no conversion was observed. This is likely caused by strong steric shielding of the Be center.

Introducing AFS ([Al(SOF)]) - a thermally stable, readily available, and catalytically active solid Lewis superacid.

Common Lewis superacids often suffer from low thermal stability or complicated synthetic protocols, requiring multi-step procedures and expensive starting materials. This prevents their large-scale application. Herein, the easy and comparably cheap synthesis of high-purity aluminium tris(fluorosulfate) ([Al(SOF)], AFS) is presented.

Ion molecule reactions in the HBr + CH system: a combined experimental and theoretical study.

Reactions in the system HBr + CH have been investigated inside a guided ion-beam apparatus under single-collision conditions. The HBr is vibrational and rotational state selected in the electronic XΠ state created by (2+1)-REMPI. Due to the exitation scheme employed different rotational states of the HBr are accessible.

Multi-wall carbon Nanotube surface-based functional nanoparticles for stimuli-responsive dual pharmaceutical compound delivery.

Carbon nanotubes (CNTs) have the potential to serve as delivery systems for medicinal substances and gene treatments, particularly in cancer treatment. Co-delivery of curcumin (CUR) and Methotrexate (MTX) has shown promise in cancer treatment, as it uses fewer drugs and has fewer side effects. This study used MTX-conjugated albumin (BSA)-based nanoparticles (BSA-MTX) to enhance and assess the efficiency of CUR.

f-Element Zintl Chemistry: Actinide-Mediated Dehydrocoupling of HSb Affords the Trithorium and Triuranium Undeca-Antimontriide Zintl Clusters [{An(Tren)}(μ-Sb)] (An = Th, U; Tren = {N(CHCHNSiPr)}).

Reaction of the cesium antimonide complex [Cs(18C6)][SbH] (, 18C6 = 18-crown-6 ether) with the triamidoamine actinide separated ion pairs [An(Tren)(L)][BPh] (Tren = {N(CHCHNSiPr)}; An/L = Th/DME (); U/THF ()) affords the triactinide undeca-antimontriide Zintl clusters [{An(Tren)}(μ-Sb)] (An = Th (), U ()) by dehydrocoupling. Clusters and provide two new examples of the Sb Zintl trianion and are unprecedented examples of molecular Sb being coordinated to anything since all previous reports featured isolated Sb Zintl trianions in separated ion quadruple formulations with noncoordinating cations. Quantum chemical calculations describe dominant ionic An-Sb interactions in and , though the data suggest that the latter exhibits slightly more covalent An-Sb linkages than the former.

Dynamics of carbene formation in the reaction of methane with the tantalum cation in the gas phase.

The controlled activation of methane has drawn significant attention throughout various disciplines over the last few decades. In gas-phase experiments, the use of model systems with reduced complexity compared to condensed-phase catalytic systems allows us to investigate the intrinsic reactivity of elementary reactions down to the atomic level. Methane is rather inert in chemical reactions, as the weakening or cleavage of a C-H bond is required to make use of methane as C-building block.

Supramolecular trapping of a cationic all-metal σ-aromatic {Bi} ring.

Aromaticity in organic molecules is well defined, but its role in metal-only rings remains controversial. Here we introduce a supramolecular stabilization approach of a cationic {Bi} rhomboid within the symmetric charge sphere of two bowl-shaped dianionic calix[4]pyrrolato indinates. Crystallographic and spectroscopic characterization, quantum chemical analysis and magnetically induced ring currents indicate σ-aromaticity in the formally tetracationic 16-valence electron [Bi] ring.

Fully Reprogrammable 2D Array of Multistate Molecular Switching Units.

Integration of molecular switching units into complex electronic circuits is considered to be the next step toward the realization of novel logic and memory devices. This paper reports on an ordered 2D network of neighboring ternary switching units represented by triazatruxene (TAT) molecules organized in a honeycomb lattice on a Ag(111) surface. Using low-temperature scanning tunneling microscopy, the bonding configurations of individual TAT molecules can be controlled, realizing up to 12 distinct states per molecule.

Multistate Dynamics and Kinetics of CO Activation by Ta in the Gas Phase: Insights into Single-Atom Catalysis.

The activation of carbon dioxide (CO) by a transition-metal cation in the gas phase is a unique model system for understanding single-atom catalysis. The mechanism of such reactions is often attributed to a "two-state reactivity" model in which the high-energy barrier of a spin state correlating with ground-state reactants is avoided by intersystem crossing (ISC) to a different spin state with a lower barrier. However, such a "spin-forbidden" mechanism, along with the corresponding dynamics, has seldom been rigorously examined theoretically, due to the lack of global potential energy surfaces (PESs).

Synthesis, in vitro antitumor evaluation and structure activity relationship of heptacoordinated amino-bis(Phenolato) Ti(IV) complexes stabilized by 2,6-dipicolinic acid.

Eighteen novel Ti(IV) complexes stabilized by different chelating amino-bis(phenolato) (ONNO, ONON, ONOO) ligands and 2,6-dipicolinic acid as a second chelator were synthesized with isolated yields ranging from 79 to 93%. Complexes were characterized by H and C-NMR spectroscopy, as well as by HRMS and X-Ray diffraction analysis. The good to excellent aqueous stability of these Ti(IV) complexes can be modulated by the substitutions on the 2-position of the phenolato ligands.

Deciphering the chemical bonding of the trivalent oxygen atom in oxygen doped graphene.

Recently, planar and neutral tricoordinated oxygen embedded in graphene has been imaged experimentally (, 2019, , 4570-4577). In this work, this unusual chemical species is studied utilizing a variety of state-of-the-art methods and combining periodic calculations with a fragmental approach. Several factors influencing the stability of trivalent oxygen are identified.