Effects of ultrasound-guided recruitment manoeuvres on postoperative pulmonary complications in laparoscopic bariatric surgery patients: study protocol for a randomised clinical trial.

Background: Lung ultrasound-guided alveolar recruitment manoeuvres (RMs) may reduce the lung ultrasound score. However, whether the use of this strategy can reduce the incidence of postoperative pulmonary complications (PPCs) in the adult obese population has not yet been tested.

Methods/design: This is a single-centre, two-arm, prospective, randomised controlled trial.

Phosphination of aryl/alkyl bromides Mn-mediated reductive C-P coupling.

Mn-mediated reductive cross-coupling of organic bromides with 2-bromo-1,3,2-diazaphospholene was developed for efficient construction of C-P bonds under mild conditions. Mechanistic studies suggested that bromides are activated by formed bis-diazaphospholene hybrid radical and polar mechanisms.

Metal-Carbon Bond Heterolysis Energy Scale for Model Palladium Catalysts.

Thermodynamic studies of transition-metal intermediates are crucial for understanding of metal-catalyzed transformations. Herein, a series of arylpalladium cyanomethanides were synthesized and characterized. Their palladium-carbon bond heterolysis energies (Δ(Pd-C)) were determined in DMSO for the first time by equilibrium methods.

Organocatalytic Hydrogen Evolution Reaction by Diazaphospholenes.

The electrochemical hydrogen evolution reaction (HER) is currently recognized as a prospective way to obtain clean energy. The electrocatalysts used currently are dominantly based on transition metals. In this work, we have demonstrated a diazaphospholene (-heterocyclic phosphine (NHP))-type small molecular organocatalyst that can catalyze the HER with a maximum current density of 130 mA·cm, an overpotential of 354 mV, and a faradaic efficiency of 90%.

Recycled Excavation Soils as Sustainable Supplementary Cementitious Materials: Kaolinite Content and Performance Implications.

In response to the environmental implications of the massive quantities of excavation soil generated by global urbanization and infrastructure development, recent research efforts have explored the repurposing of calcined excavation soils as sustainable supplementary cementitious materials (SCMs). As it is still at an early stage, current research lacks systematic analysis across diverse soil deposits regarding their reactivity and mechanical properties within cementitious binders, despite recognized geographical variability in kaolinite content. Through comprehensive experimentation with soils sourced from four major southern Chinese cities, this study presents a pioneering assessment of the compressive strength, pozzolanic reactivity (X-ray diffraction, Fourier-transform infrared spectroscopy, solid-state nuclear magnetic resonance), and microstructural development (mercury intrusion porosimetry, scanning electron microscopy) of mortars modified by various calcined excavation soils (up to 28 days curing).

Preparation and Application of Nano-Calcined Excavation Soil as Substitute for Cement.

Rapid urbanization in many cities has produced massive amounts of problematic excavation soil. The direct disposal of untreated excavation soil often leads to significant land use and severe environmental concerns. A sustainable solution is to transform the soil waste into high-quality nano-calcined excavation soil (NCES) for application as a substitute for cement in construction.

Hydroxylamine-Mediated C(sp)-H Trifluoromethylation of Terminal Alkenes.

Introduction of the trifluoromethyl (CF) group into organic compounds has garnered substantial interest because of its significant role in pharmaceuticals and agrochemicals. Here, we report a hydroxylamine-mediated radical process for C(sp)-H trifluoromethylation of terminal alkenes. The reaction shows good reactivity, impressive E/Z selectivity (up to >20 : 1), and broad functional group compatibility.

Phosphonium-Catalyzed Monoreduction of Bisphosphine Dioxides: Origin of Selectivity and Synthetic Applications.

Controlling product selectivity in successive reactions of the same type is challenging owing to the comparable thermodynamic and kinetic properties of the reactions involved. Here, the synergistic interaction of the two phosphoryl groups in bisphosphine dioxides (BPDOs) with a bromo-phosphonium cation was studied experimentally to provide a practical tool for substrate-catalyst recognition. As the eventual result, we have developed a phosphonium-catalyzed monoreduction of chiral BPDOs to access an array of synthetically useful bisphosphine monoxides (BPMOs) with axial, spiro, and planar chirality, which are otherwise challenging to synthesize before.

Deoxygenation of Phosphine Oxides by P/P═O Redox Catalysis via Successive Isodesmic Reactions.

Deoxygenation of phosphine oxides is of great significance to synthesis of phosphorus ligands and relevant catalysts, as well as to the sustainability of phosphorus chemistry. However, the thermodynamic inertness of P═O bonds poses a severe challenge to their reduction. Previous approaches in this regard rely primarily on a type of P═O bond activation with either Lewis/Brønsted acids or stoichiometric halogenating reagents under harsh conditions.

Revisiting the Electrochemistry of TEMPOH Analogues in Acetonitrile.

Hydroxylamines, represented by 1-hydroxy-2,2,6,6-tetramethylpiperidine (TEMPOH), are widely involved as active species in various chemical and electrochemical oxidations. The electrochemical behavior of TEMPOH is crucial to understanding the mechanisms of TEMPO-mediated redox sequences. However, compared to abundant studies on TEMPOH electrochemistry in aqueous solutions, the sole value of its oxidation potential (TEMPOH) in organic solutions was reported to be 0.

Discovery of ABBV-3373, an Anti-TNF Glucocorticoid Receptor Modulator Immunology Antibody Drug Conjugate.

Using a convergent synthetic route to enable multiple points of diversity, a series of glucocorticoid receptor modulators (GRM) were profiled for potency, selectivity, and drug-like properties . Despite covering a large range of diversity, profiling the nonconjugated small molecule was suboptimal and they were conjugated to a mouse antitumor necrosis factor (TNF) antibody using the MP-Ala-Ala linker. Screening of the resulting antibody drug conjugates (ADCs) provided a better assessment of efficacy and physical properties, reinforcing the need to conduct structure-activity relationship studies on the complete ADC.

Catalytic Vilsmeier-Haack Reactions for C1-Deuterated Formylation of Indoles.

The Vilsmeier-Haack reaction is a powerful tool to introduce formyl groups into electron-rich arenes, but its wide application is significantly restricted by stoichiometric employment of caustic POCl. Herein, we reported a catalytic version of the Vilsmeier-Haack reaction enabled by a P(III)/P(V)═O cycle. This catalytic reaction provides a facile and efficient route for the direct construction of C1-deuterated indol-3-carboxaldehyde under mild conditions with stoichiometric DMF-d7 as the deuterium source.

Synthetic applications of NHPs: from the hydride pathway to a radical mechanism.

The unique heterocyclic skeletons of N-heterocyclic phosphines (NHPs) endow them with excellent hydridic reactivity, which has enabled NHPs to be applied in a great array of catalytic hydrogenations of unsaturated substrates in the past few decades. Recently, applications of NHPs in radical reductions, especially in a catalytic fashion, have emerged as a promising forefront area. This new reaction pattern, distinctive from but complementary to the well-established hydride pathway, can greatly expand the reaction scope to σ-bond scission.

LncRNA TUG1 Promoted Stabilization of BAG5 by Binding DDX3X to Exacerbate Ketamine-Induced Neurotoxicity.

As a clinically widely used anesthetic, ketamine (KET) has been reported to cause neurotoxicity in patients. Our work aimed to probe the function of long-chain non-coding RNA taurine-upregulated gene 1 (lncRNA TUG1) in KET-induced neurotoxicity. HT22 cells were subjected to KET to build the cell model.

Diazaphospholene-Catalyzed Hydrodefluorination of Polyfluoroarenes with Phenylsilane via Concerted Nucleophilic Aromatic Substitution.

The metal-free catalytic C-F bond activation of polyfluoroarenes was achieved with diazaphospholene as the catalyst and phenylsilane as the terminal reductant. Density functional theory calculations suggested a concerted nucleophilic aromatic substitution mechanism.

Recent progress in reactivity study and synthetic application of N-heterocyclic phosphorus hydrides.

N-heterocyclic phosphines (NHPs) have recently emerged as a new group of promising catalysts for metal-free reductions, owing to their unique hydridic reactivity. The excellent hydricity of NHPs, which rivals or even exceeds those of many metal-based hydrides, is the result of hyperconjugative interactions between the lone-pair electrons on N atoms and the adjacent σ(P-H) orbital. Compared with the conventional protic reactivity of phosphines, this umpolung P-H reactivity leads to hydridic selectivity in NHP-mediated reductions.

Diazaphosphinyl radical-catalyzed deoxygenation of α-carboxy ketones: a new protocol for chemo-selective C-O bond scission mechanism regulation.

C-O bond cleavage is often a key process in defunctionalization of organic compounds as well as in degradation of natural polymers. However, it seldom occurs regioselectively for different types of C-O bonds under metal-free mild conditions. Here we report a facile chemo-selective cleavage of the α-C-O bonds in α-carboxy ketones by commercially available pinacolborane under the catalysis of diazaphosphinane based on a mechanism switch strategy.

Novel Fe-based metal-organic cluster-derived iron oxides/S,N dual-doped carbon hybrids for high-performance lithium storage.

Metal-organic frameworks (MOFs) have been extensively used in the fabrication of new advanced electrode materials for lithium ion batteries (LIBs). However, low-productivity and high-cost are some of the main challenges of MOF-derived electrodes. Herein, we report a simple solvothermal procedure to fabricate novel Fe4-based metal-organic clusters (Fe-MOCs) with their subsequent conversion to an S,N dual-doped carbon framework incorporating iron oxides under a N2 atmosphere (namely Fe2O3@Fe3O4-SNC).

Defect Engineering Enhances the Charge Separation of CeO Nanorods toward Photocatalytic Methyl Blue Oxidation.

Defect-rich photocatalytic materials with excellent charge transfer properties are very popular. Herein, Sm-doped CeO nanorods were annealed in a N atmosphere to obtain the defective Sm-doped CeO photocatalysts (Vo-Sm-CeO). The morphology and structure of Vo-Sm-CeO were systematically characterized.

Bonding Energetics of Palladium Amido/Aryloxide Complexes in DMSO: Implications for Palladium-Mediated Aniline Activation.

Thermodynamic knowledge of the metal-ligand (M-L) σ-bond strength is crucial to understanding metal-mediated transformations. Here, we developed a method for determining the Pd-X (X=OR and NHAr) bond heterolysis energies (ΔG (Pd-X)) in DMSO taking [(tmeda)PdArX] (tmeda=N,N,N',N'-tetramethylethylenediamine) as the model complexes. The ΔG (Pd-X) scales span a range of 2.

Holistic Prediction of the pK in Diverse Solvents Based on a Machine-Learning Approach.

While many approaches to predict aqueous pK values exist, the fast and accurate prediction of non-aqueous pK values is still challenging. Based on the iBonD experimental pK database (39 solvents), a holistic pK prediction model was established using machine learning. Structural and physical-organic-parameter-based descriptors (SPOC) were introduced to represent the electronic and structural features of the molecules.

Exploiting the radical reactivity of diazaphosphinanes in hydrodehalogenations and cascade cyclizations.

The remarkable reducibility of diazaphosphinanes has been extensively applied in various hydrogenations, based on and yet limited by their well-known hydridic reactivity. Here we exploited their unprecedented radical reactivity to implement hydrodehalogenations and cascade cyclizations originally inaccessible by hydride transfer. These reactions feature a broad substrate scope, high efficiency and simplicity of manipulation.

Predicting Absolute Rate Constants for Huisgen Reactions of Unsaturated Iminium Ions with Diazoalkanes.

The kinetics and stereochemistry of the reactions of iminium ions derived from cinnamaldehydes and MacMillan's imidazolidinones with diphenyldiazomethane and aryldiazomethanes were investigated experimentally and with DFT calculations. The reactions of diphenyldiazomethane with iminium ions derived from MacMillan's second-generation catalysts gave 3-aryl-2,2-diphenylcyclopropanecarbaldehydes with yields >90 % and enantiomeric ratios of ≥90:10. Predominantly 2:1 products were obtained from the corresponding reactions with monoaryldiazomethanes.