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A selective direct arylation of the different Csp2‐H bonds of imidazo[2,1‐b]thiazole with (hetero) aryl halides can be achieved simply by switching from a palladium catalyst system to the use of stoichiometric amounts of copper. The observed selectivity, also rationalized by DFT calculations, can be explained by a change in the mechanistic pathways between electrophilic palladation and base‐promoted C−H metalation. [ABSTRACT FROM AUTHOR]

Aryl radicals play a pivotal role as reactive intermediates in chemical synthesis, commonly arising from aryl halides and aryl diazo compounds. Expanding the repertoire of sources for aryl radical generation to include abundant and stable organoboron reagents would significantly advance radical chemistry and broaden their reactivity profile. While traditional approaches utilize stoichiometric oxidants or photocatalysis to generate aryl radicals from these reagents, electrochemical conditions have been largely underexplored. Through rigorous mechanistic investigations, we identified fundamental challenges hindering aryl radical generation. In addition to the high oxidation potentials of aromatic organoboron compounds, electrode passivation through radical grafting, homocoupling of aryl radicals, and decomposition issues were identified. We demonstrate that pulsed electrosynthesis enables selective and efficient aryl radical generation by mitigating the fundamental challenges. Our discoveries facilitated the development of the first electrochemical conversion of aryl potassium trifluoroborate salts into aryl C−P bonds. This sustainable and straightforward oxidative electrochemical approach exhibited a broad substrate scope, accommodating various heterocycles and aryl chlorides, typical substrates in transition‐metal catalyzed cross‐coupling reactions. Furthermore, we extended this methodology to form aryl C−Se, C−Te, and C−S bonds, showcasing its versatility and potential in bond formation processes. [ABSTRACT FROM AUTHOR]

Background: Noninvasive ventilation (NIV) in COVID-19 patients outside of intensive care unit (ICU) settings was a feasible support during the pandemic outbreak. The aim of this study was to assess the effectiveness of an "on the job" NIV training program provided to 66 nurses working in 3 COVID-19 wards in an Italian university hospital. Methods: A quasi-experimental longitudinal before–after study was designed. The NIV Team education program, provided by expert ICU nurses, included: 3 h sessions of training on the job during work-shifts about the management of helmet-continuous positive airway pressure (CPAP) Venturi systems, and NIV with oronasal and full-face masks. An eleven-item "brief skills self-report tool" was administered before and after the program to explore the perception of NIV education program attendees about their level of skills. Results: In total, 59 nurses responded to the questionnaire. There was an improvement in the skill levels of the management of Helmet-CPAP (median before training 2, inter-quartile range (IQR) 0–6; median after training 8, IQR 3–9; p < 0.0001), and mask-NIV (median before training 2, IQR 0–6; median after training 8, IQR 3–9; p < 0.0001). Conclusions: Training on the job performed by expert ICU nurses can be a valuable and fast means to implement new Helmet-CPAP and mask-NIV skills outside of ICUs. [ABSTRACT FROM AUTHOR]

A selective direct arylation of the different Csp2-H bonds of imidazo[2,1-b]thiazole with (hetero) aryl halides can be achieved simply by switching from a palladium catalyst system to the use of stoichiometric amounts of copper. The observed selectivity, also rationalized by DFT calculations, can be explained by a change in the mechanistic pathways between electrophilic palladation and base-promoted C-H metalation., (© 2024 The Authors. ChemistryOpen published by Wiley-VCH GmbH.)

Aryl radicals play a pivotal role as reactive intermediates in chemical synthesis, commonly arising from aryl halides and aryl diazo compounds. Expanding the repertoire of sources for aryl radical generation to include abundant and stable organoboron reagents would significantly advance radical chemistry and broaden their reactivity profile. While traditional approaches utilize stoichiometric oxidants or photocatalysis to generate aryl radicals from these reagents, electrochemical conditions have been largely underexplored. Through rigorous mechanistic investigations, we identified fundamental challenges hindering aryl radical generation. In addition to the high oxidation potentials of aromatic organoboron compounds, electrode passivation through radical grafting, homocoupling of aryl radicals, and decomposition issues were identified. We demonstrate that pulsed electrosynthesis enables selective and efficient aryl radical generation by mitigating the fundamental challenges. Our discoveries facilitated the development of the first electrochemical conversion of aryl potassium trifluoroborate salts into aryl C-P bonds. This sustainable and straightforward oxidative electrochemical approach exhibited a broad substrate scope, accommodating various heterocycles and aryl chlorides, typical substrates in transition-metal catalyzed cross-coupling reactions. Furthermore, we extended this methodology to form aryl C-Se, C-Te, and C-S bonds, showcasing its versatility and potential in bond formation processes., (© 2024 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)