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The addition of phenyl lithium (PhLi) to an aromatic 1,3,2,5-diazadiborinine (1) afforded isolable ionic species 2, which can be deemed as an inorganic analogue of a Janovsky complex. X-ray diffraction analysis and DFT studies of 2 indicate the delocalization of π-type electrons mainly over the C–B–C unit in the central B2C2N2 six-membered ring. The reactions of 2 with methyl iodide (MeI) and chloro(tricyclohexylphosphine)gold(i) (Cy3PAuCl) gave 3 bearing a B–Me bond and 4 featuring a B–Au bond, respectively, demonstrating the nucleophilic properties of the tricoordinate boron center in 2. [ABSTRACT FROM AUTHOR]

A novel fluorescence turn-on strategy for glucose sensing is demonstrated. The fluorescence of a perylene probe could be quenched by the silver nanoparticles (Ag NPs). The Ag NPs could be etched by H2O2 generated from the enzymatic oxidation of glucose. And efficient probe fluorescence recovery was detected. [ABSTRACT FROM AUTHOR]

A metal-free tandem double hydrophosphination of extended conjugated indandiones has been established. Mechanistic investigations confirmed the consecutive manner of the nucleophilic addition reaction. Complexation of the generated keto-diphosphine resulted in the formation of an unexpected tridentate bridging ligand with an anionic P,O-bidentate and a neutral P-monodentate coordination mode on two palladium units. In the presence of an external chiral auxiliary, the coordinated diphosphines could be separated into their enantiomeric forms. [ABSTRACT FROM AUTHOR]

In this work, we report the successful construction of two chiral porous metal-metallosalan frameworks (1 and 2) by using dipyridylfunctionalized chiral Al(salen) and Mn(salen) separately, and then a composite crystal MOF 3 was constructed with 1 inside, which was encapsulated by 2 outside. The resulting composite crystal appeared to be highly enantioselective for the alkene epoxidation/epoxide aminolysis reactions with a maximum ee of 97%. [ABSTRACT FROM AUTHOR]

A catalytic asymmetric hydroarsination reaction of an activated alkene viz. (E)-nitrostyrene was developed using chiral PCP Pt-, Pd- and Ni-pincer complexes as catalysts. The corresponding chiral tertiary arsine adduct was obtained in ees of up to 80% under mild reaction conditions using the PCP Ni–Cl pincer catalyst. The arsine adduct was furnished with catalyst loadings of 1–5 mol% and the reaction duration ranging from ＜5 min to 180 min. The subsequent coordination of the hydroarsination product to gold(i) chloride allowed for the confirmation of the stereochemistry of the arsine adduct via crystallographic analysis. [ABSTRACT FROM AUTHOR]

Cyclopalladation of the pyridyl-substituted chiral phosphine sulfide (N–P=S) and oxide (N–P=O) compounds afforded the asymmetric N–C(sp3)*–S and N–C(sp3)*–O pincer complexes. When applied as catalysts in asymmetric hydrophosphination, the newly developed aliphatic pincer catalyst could be recycled over three runs and obtained in large quantities via a one-pot “self-breeding” catalytic protocol. [ABSTRACT FROM AUTHOR]

The reaction of germylone (L)Ge (1) [L = 3-Ad-1-{C(tBu) = N(Mes)}C3H4N2] with 1 equivalent of MeOTf afforded a germyliumylidene ion [(L)GeMe]+OTf− (2), while reactions with M(CO)5(thf) (M = Cr, Mo, W) gave the corresponding germylone-metal complexes [(L)Ge]M(CO)5 (3–5). The former possesses a pyramidal Ge center, whereas the latter display a planar geometry around the Ge atom. Computational studies showed a unique bonding interaction between 1 and the M(CO)5 unit, which involves a σ-donation as well as a weak π-back-donation. [ABSTRACT FROM AUTHOR]

Gold-catalyzed hydroimination of terminal alkynes, giving rise to anti-Markovnikov adducts concomitant with unstable Markovnikov adducts is described. The elementary step can be applied for the construction of pyridine derivatives from ammonia and alkynes. [ABSTRACT FROM AUTHOR]

Herein, we discover the new reactivity of the 1,3,5-triazine moiety reacting with a phenol group and report the development of biocompatible and catalyst-free triazine-pyridine chemistry (TPC) for tyrosine labelling under physiological conditions and profiling in the whole proteome. TPC exhibited high tyrosine chemoselectivity in biological systems after cysteine blocking, displayed potential in tyrosine-guided protein labelling, and had bio-compatibility in live cells. [ABSTRACT FROM AUTHOR]

Bisphosphine oxides formed highly active asymmetric Heck catalysts, which were applied in asymmetric synthesis of pharmacologically active azacycles. Olefin insertion proceeded via cis pathways, different from P,N-ligands. [ABSTRACT FROM AUTHOR]

Modulated synthesis and isoreticular expansion of Th-MOFs enable the stepwise construction of hierarchical complexes in which porosity and functionality can be fine-tuned, affording new Th-MOFs with a record high void space (74.0%), the largest surface area (3396.5 m2 g−1) among thorium materials, and excellent adsorption capacities toward radioactive iodine. [ABSTRACT FROM AUTHOR]

A simple nanopore modification and sensing strategy was developed for the detection of miRNAs. This preparation and sensing approach provides a quick, simple and facile tool for the detection of specific biomolecules with high sensitivity and selectivity, and may find a wide range of applications in bio-analysis. [ABSTRACT FROM AUTHOR]

The fabrication of a perovskite oxide with a tunable pore-size was implemented by a general inorganic salt-template strategy. As a proof-of-concept, hierarchically porous PrBa0.5Sr0.5Co1.5-Fe0.5O5+δ (PBSCF) with a surface area of 148 m2 g−1 was successfully prepared, which exhibited remarkable electrocatalytic performance for the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

An ultrafine ruthenium nanocrystal (RuNC) was fabricated via thermal annealing tris(2,2′-bipyridine)ruthenium dichloride with cyanuric acid. The as-obtained RuNC features a small diameter of ∼2 nm and high crystallinity. As an electrocatalyst for the hydrogen evolution reaction, the ultrafine RuNC exhibited remarkable performance in both acidic and alkaline media. [ABSTRACT FROM AUTHOR]

Mechanochemistry has been established to be an environmentally-friendly way of conducting reactions in a solvent-free manner. The development of mechanochemical orthogonal reactions, in which multiple reagents are milled together, can be a powerful strategy to selectively yield the desired product. Such orthogonal syntheses are rare, especially those involving main group frameworks – based on bonds other than carbon – which are yet to be reported. Herein, we demonstrate the direct formation of air- and moisture-stable cyclophosph(v)azanes enabled by an orthogonal “one-step one-pot” mechanochemical reaction. In addition, detailed hydrolytic- and air-stability studies, conducted over one and 12 months, respectively, revealed high robustness of these compounds. [ABSTRACT FROM AUTHOR]

Here, we present our recent progress on the synthesis, crystal structure, physical properties and DFT calculations of a novel large pyrene-fused N-heteroacene (15RINGS) with 15 aromatic six-membered rings linearly fused in one row. The long conjugated backbone (more than 35 Å) of 15RINGS possesses a dual-bending feature (the bending angle is about 13.2°). [ABSTRACT FROM AUTHOR]

Single Au nanowire electrodes and single Pt@Au nanowire electrodes showed steady-state voltammetric responses and a fast electron-transfer rate, which have been used to fabricate an E-DNA sensor and investigate the oxygen reduction reaction at the single nanowire level. [ABSTRACT FROM AUTHOR]

A new approach for the sensitive and selective sensing of a protein has been developed. Cytochrome c could quench the fluorescence of a fluorophore labeled aptamer efficiently. The specific binding between the aptamer and the target protein resulted in a turn-on emission signal, which could be used for protein quantification. [ABSTRACT FROM AUTHOR]