36 research outputs found

    Cyclic Hypervalent Iodine Reagents and Iron Catalysts: The Winning Team for Late-Stage C-H Azidation

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    1+1=3: by combining the exceptional properties of benziodoxolone reagents and iron catalysts, Sharma and Hartwig have achieved an important breakthrough for the late-stage C-Hazidation of complex molecules. Nevertheless, moderate yields and selectivities were still observed for some substrates, and our understanding of the reaction mechanism remains underdeveloped. Indeed, the potential of combining base-metal catalysts and cyclic hypervalent iodine reagents for the discovery of new reactions has just begun to be investigated, and many more exciting discoveries await us in the future. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

    Azidation of beta-Keto Esters and Silyl Enol Ethers with a Benziodoxole Reagent

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    The efficient azidation of beta-keto esters and silyl enol ethers using a benziodoxole-derived azide transfer reagent is reported. The azidation of cyclic beta-keto esters could be achieved in up to quantitative yields in the absence of any catalyst. In the case of less reactive linear beta-keto esters and silyl enol ethers, complete conversion and good yields could be obtained by using a zinc catalyst

    Enantioselective Synthesis of Polycyclic Carbocycles via an Alkynylation-Allylation-Cyclization Strategy

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    A new general three-stage strategy to access polycyclic ring systems bearing all-carbon quaternary centers with high enantioselectivity is reported. The required starting materials were readily accessed in racemic form through the alpha-alkynylation of ketoesters with EBX (EthynylBenziodoXolone) hypervalent iodine reagents. A Pd-catalyzed asymmetric decarboxylation allylation was then achieved in high yields and enantioselectivities with Trosts biphosphine ligands. Finally, transition-metal catalyzed cyclization of the obtained chiral enynes gave access to fused and spiro polycyclic ring systems constituting the core of many bioactive natural products

    Enantioselective Synthesis of Homoallylic Azides and Nitriles via Palladium-Catalyzed Decarboxylative Allylation

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    Azides and nitriles are important building blocks for the synthesis of nitrogen-containing bioactive compounds. The first example of enantioselective palladiumcatalyzed decarboxylative allylation of alpha-azido and cyano beta-ketoesters is reported. Indanone derivatives were obtained in 50-88% yield/77-97% ee and 46-98% yield/78-93% ee for azide and nitrile substituents, respectively. The required starting materials were synthesized in one step from ketoesters via electrophilic azidation and cyanation using benziodoxole hypervalent iodine reagents. The products could be easily converted into useful nitrogen-containing building blocks, such as triazoles, amides, or alpha- and beta- amino ketones

    Taming Hypervalent Bonds and Strained Rings for Catalysis and Synthesis

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    Improving the synthesis of complex organic molecules is essential for progress in many fields such as medicine, agrochemicals or materials. Since 2007, our laboratory has been focusing on the development of non-classical bond disconnections based on the use of small, energy-loaded organic molecules: hypervalent iodine reagents and strained rings. In this overview article, we report our progress since 2011 in these areas. The use of cyclic hypervalent iodine reagents has been extended to the C2-selective alkynylation of indoles, the domino cyclization alkynylation of allenes, the alkynylation of thiols and the azidation of carbonyl compounds. Amino-substituted aminocyclopropanes and aminocyclobutanes were used in [3+2] and [4+2] annulations to access nitrogen-rich building blocks, including nucleoside analogues. The first example of dynamic kinetic [3+2] annulation of aminocyclopropanes with both enol ethers and aldehydes was also reported

    Perspectives on Mentorship – Reinventing Mentoring in Arts and Creative Industries Management.

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    The book Perspectives on Mentorship – Reinventing Mentoring in Arts and Creative Industries Management offers a holistic view with multiple perspectives to the topic of mentorship in arts and cultural context. It can be used as a course book for mentorship programmes, providing further knowledge for anyone working in mentorship or planning to build a mentorship programme in the context of arts management education within art or cultural institutions. It provides a unique exploration of this subject by presenting different perspectives, raising thought provoking questions, and examining ways to manage a mentoring programme. It is important to remember that mentoring does not happen by itself, and that it requires management and intervention in order to be sustainable. University students interested in arts management will find the book invaluable in obtaining a better understanding of how mentoring could be approached and help them in the development of their professional identity. It does not present one universal truth or method, but instead is about sharing experiences. From the academic perspective, the book encourages readers to approach mentoring with an open mind, offering tools to reflect on the process of building programmes around the core of mentoring – a dynamic human relationship which affects the identity of both parties – and then to build on the different layers around that foundation. The book seeks to provide insights into the different layers that are created during the mentoring process. It poses a variety of questions that can apply to specific programmes and helps readers understand how to effectively manage and sustain mentorship relationships.EUROPEAN COMMISSION–EACEA 2020: Ref. 2020-1-EE01-KA203-078003. Reinventing Mentoring in Arts Management. (2020-2023

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat
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