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Molecular Dynamics (MD) simulations constitute a powerful tool that provides a 3D perspective of the dynamical behavior of chemical systems. Herein the first MD study of the dynamics of a catalytic organometallic system, in micellar media, is presented. The challenging methane catalytic functionalization into ethyl propionate through a silver‐catalyzed process has been targeted as the case study. The intimate nature of the micelles formed with the surfactants sodium dodecylsulfate (SDS) and potassium perfluorooctane sulfonate (PFOS) has been ascertained, as well as the relative distribution of the main actors in this transformation, namely methane, the diazo reagent and the silver catalyst, the latter in two different forms: the initial compound and a silver‐carbene intermediate. Catalyst deactivation occurs with halide containing surfactants dodecyltrimethylammonium chloride (DTAC) and Triton X‐100. Computed simulations allow explaining the experimental results, indicating that micelles behave differently regarding the degree of accumulation and the local distribution of the reactants and their effect in the molecular collisions leading to net reaction. [ABSTRACT FROM AUTHOR]

Purpose To compare pain incidence and changes in pain scores with fentanyl versus placebo as pre-emptive treatment during turning and 30 min post-turning in mechanically ventilated critically ill patients. Methods We performed a randomized, double-blind, parallel-group, placebo-controlled clinical trial in the intensive care unit of a university hospital. Seventy-five mechanically ventilated patients were randomized to an intervention group (fentanyl) or a control group (placebo). Patients in the intervention group received 1 [micro]g/kg (medical patients) or 1.5 [micro]g/kg (surgical patients) of fentanyl 10 min before turning. Pain indicators were assessed using the behavioral pain scale. Safety was assessed by determining the frequency and severity of pre-defined adverse events. Pain was evaluated at rest (T0), at turn start and end (T1 and T2) and at 5, 15 and 30 min post-turning (T3, T4 and T5). Results The two groups had similar baseline characteristics. The area under the curve for BPS values was significantly smaller in the fentanyl group than in the control group [median and interquartile range (IQR): 132 (108-150) vs. 147 (125-180); p = 0.016, respectively]. Nineteen non-serious adverse events were recorded in 14 patients, with no significant between-group differences (23 % fentanyl group vs. 14 % control group; p = 0.381). Conclusions These results suggest an intravenous bolus of fentanyl of 1 [micro]g/kg for medical patients or 1.5 [micro]g/kg for surgical patients reduces the incidence of turning-associated pain in critically ill patients on mechanical ventilation. ClinicalTrials.gov: NCT 01950000., Author(s): Gemma Robleda [sup.1], Ferran Roche-Campo [sup.2] [sup.3], Maria-Àngels Sendra [sup.2], Marta Navarro [sup.2], Ana Castillo [sup.2], Ainhoa Rodríguez-Arias [sup.4], Elena Juanes-Borrego [sup.4], Ignasi Gich [sup.5] [sup.6] [sup.7], Gerard Urrutia [...]

The trapping of the elusive vinylogous position of a vinyl carbene with an aliphatic C(sp3)−H bond has been achieved for the first time during a silver‐catalyzed carbene/alkyne metathesis (CAM) process. A Tpx‐containing silver complex first promotes the generation of a donor‐acceptor silver carbene which triggers CAM, generating a subsequent donor‐donor vinyl silver carbene species, which then undergoes a selective vinylogous C(sp3)−H bond insertion, leading to the synthesis of a new family of benzoazepines. Density functional theory (DFT) calculations unveil the reaction mechanism, which allows proposing that the C−H bond insertion reaction takes place in a stepwise manner, with the hydrogen shift being the rate determining step. [ABSTRACT FROM AUTHOR]