Germylene complexes of tungsten pentacarbonyls W(CO)5{double bond, long}GeCl2 and W(CO)5{double bond, long}Ge{double bond, long}W(CO)5: Electrochemical synthesis and quantum-chemical computations

Convenient synthetic route to prepare the germylene complexes of tungsten pentacarbonyls, W(CO)5{double bond, long}GeCl2 and W(CO)5{double bond, long}Ge{double bond, long}W(CO)5, electrochemically is developed. Combined quantum-chemical/IR spectroscopic approach is used for identification of the synthesized compounds. Good agreement between theoretical and experimental spectra can be regarded as one of the proofs of their supposed structures. © 2007 Elsevier B.V. All rights reserved

Electrochemical ortho functionalization of 2-phenylpyridine with perfluorocarboxylic acids catalyzed by palladium in higher oxidation states

The electochemical oxidation of palladium acetate or palladium perfluoroacetate in the presence of 2-phenylpyridine promotes catalytic ortho C-H substitution reactions. As possible intermediates, Pd(II) metallacycles with Pd-bound acetate, perfluoroacetate, and perfluoroheptanoate substituents have been isolated and characterized: binuclear [(PhPy)Pd(μ-OAc)]2 and [(PhPy)Pd(μ-TFA)]2 and mononuclear [(PhPy)Pd(TFA)](CH 3CN), [(PhPy)Pd(TFA)](PhPy), and [(PhPy)Pd(PFH)](PhPy). The fluorinated derivatives were found to exist in solvent-dependent equilibria between mononuclear and binuclear forms. Cyclic voltammetry was used to elucidate redox properties of the palladacycles and the oxidation route to the final products. © 2013 American Chemical Society

Palladium Nanoparticles–Polypyrrole Composite as Effective Catalyst for Fluoroalkylation of Alkenes

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. Abstract: Palladium nanoparticles–polypyrrole composite (Pd/PPy) catalyzes the addition of perfluoroalkyl halides to olefins to produce a variety of products with good yields. An effective fluoroalkylation technique tested with various olefins, fluoroalkyl halides and Pd/PPy was developed. The reaction proceeds highly efficient under mild phosphine-free reaction conditions with different substrates, easy catalyst recycling and provides a general and straightforward access to fluoroalkylated products. Furthermore, we were able to control whether the addition of perfluoroalkyl occurs with various monomer (fluoroalkylated alkene or alkane with RF and OH moieties) or dimer formation (under electrochemical conditions). Graphical Abstract: [Figure not available: see fulltext.]

A Ni(III) complex stabilized by silica nanoparticles as an efficient nanoheterogeneous catalyst for oxidative C-H fluoroalkylation

© The Royal Society of Chemistry 2016.We have developed NiIII-doped silica nanoparticles ([(bpy)xNiIII]@SiO2) as a recyclable, low-leaching, and efficient oxidative functionalization nanocatalyst for aromatic C-H bonds. The catalyst is obtained by doping the complex [(bpy)3NiII] on silica nanoparticles along with its subsequent electrooxidation to [(bpy)xNiIII] without an additional oxidant. The coupling reaction of arenes with perfluoroheptanoic acid occurs with 100% conversion of reactants in a single step at room temperature under nanoheterogeneous conditions. The catalyst content is only 1% with respect to the substrates under electrochemical regeneration conditions. The catalyst can be easily separated from the reaction mixture and reused a minimum of five times. The results emphasize immobilization on the silica support and the electrochemical regeneration of NiIII complexes as a facile route for developing an efficient nanocatalyst for oxidative functionalization

Redox trends in cyclometalated palladium(II) complexes

© The Royal Society of Chemistry. A series of diverse binuclear and mononuclear cyclometalated palladium(ii) complexes of different structure was investigated by electrochemical techniques combined with density functional theory (DFT) calculations. The studies including cyclic and differential pulse voltammetry, X-ray structure analysis and quantum chemical calculations revealed a regularity of the complexes oxidation potential on the metal-metal distance in the complexes: the larger Pd-Pd distance, the higher oxidation potentials. The reduction potentials feature unusually high negative values while no correlation depending on the structure could be observed. These results are in a good agreement with the electron density distribution in the complexes. Additionally, ESR data obtained for the complexes upon oxidation is reported

Redox trends in cyclometalated palladium(II) complexes

© The Royal Society of Chemistry.A series of diverse binuclear and mononuclear cyclometalated palladium(ii) complexes of different structure was investigated by electrochemical techniques combined with density functional theory (DFT) calculations. The studies including cyclic and differential pulse voltammetry, X-ray structure analysis and quantum chemical calculations revealed a regularity of the complexes oxidation potential on the metal-metal distance in the complexes: the larger Pd-Pd distance, the higher oxidation potentials. The reduction potentials feature unusually high negative values while no correlation depending on the structure could be observed. These results are in a good agreement with the electron density distribution in the complexes. Additionally, ESR data obtained for the complexes upon oxidation is reported

Silica Nanospheres Coated by Ultrasmall Ag⁰Nanoparticles for Oxidative Catalytic Application

© 2017 Elsevier B.V. The present work introduces optimal modifiсation of core-shell composite nanomaterial, where small (2–8 nm) Ag 0 nanoparticles are deposited onto large (about 140 nm) silica spheres for application in oxidative catalysis. The size of Ag 0 and density of its deposition onto silica spheres was modified by the post treatment of initially deposited Ag 0 (about 30 nm) by hydrogen peroxide in specific conditions. The comparison of catalytic effect of the post-treated and initial SN-Ag 0 in electrochemical phosphonation of benzo(thia)oxazoles by diethyl phosphite in oxidative conditions revealed the difference between the composite nanoparticles. In particular, the post-treated SNs-Ag 0 nanoparticles exhibit efficient catalytic effect in oxidative conditions resulting in facile and green method for synthesis of phosphonated benzooxa(thia)zoles, while no catalytic effect is observed under the use of larger Ag 0 nanoparticles deposited onto silica spheres. The use of Ag 0 -based nanomaterial in oxidative catalysis had been never demonstrated before

Характеристика COVID-19 у детей: первый опыт работы в стационаре Санкт-Петербурга

Objective: to identify the clinical, laboratory and epidemiological features of the new coronavirus (CV) infection in the provision of specialized medical care to children in the megalopolis of the Russian Federation. Methods: 674 cases of hospitalization of patients from birth to 17 years old inclusive with confirmed COVID-19 in the period from March 26 to June 26, 2020 in a children’s multidisciplinary hospital in St. Petersburg. Diagnostics of SARS-COV-2 in upper respiratory tract (URT) smears was carried out by PCR (a set of reagents for detecting RNA of coronavirus 2019-nCoV by PCR with hybridization-fluorescence detection “Vector-PCRRV-2019-nCoV-RG”). Patients underwent 4 (3; 5) repeated examinations depending on the diagnosis of the referral, as well as the duration of the convalescent virus carriage. The analysis of the severity of the course of the disease, the main clinical manifestations and their relationship with the development of pneumonia, as well as the epidemiological features of COVID-19 in children. The duration of inpatient treatment, outcomes and the need for intensive care are described. Changes in a number of laboratory parameters on analyzers made in the USA were assessed: a clinical blood test on a hematological one - Coulter UniCel (Beckman Coulter), a biochemical blood test on a biochemical one - Uni Cel DxC (Beckman Coulter), a coagulogram on a hemostasis analyzer (Instrumentation Laboratory). Results: Overall, there was a favorable course of COVID-19 in children. Intensive therapy was required only in 3.6% of cases with a total mortality rate of 0.15%, Kawasakilike syndrome was recorded in 0.3% of cases. In 1/3 of patients, prolonged viral shedding from the upper respiratory tract was detected. In children, intrafamilial infection from adults was in the lead; schoolchildren accounted for half of all hospitalizations. A distinctive feature of the new infection was mild clinical symptoms with fever and catarrhal symptoms up to 4/5 of cases, gastrointestinal symptoms - in every third patient. There were no significant differences in the severity of the disease by age. Pneumonia, diagnosed in ¾ cases by computed tomography, complicated the course in 13.1% of cases. The defeat of the lungs was accompanied by fever and dry cough, and in a more severe course: desaturation, chest pains, a feeling of insufficiency of inspiration. The age peaks of the incidence of pneumonia were revealed: at 4, 9, 12 years old and at the age of 17 years, the maximum (in 1/3 of cases). Laboratory changes were insignificant and quickly reversible. Conclusion: the course of COVID-19 in children in the megalopolis of Russia is comparable with foreign information. However, taking into account the experience of “Spanish ‘flu”, it is possible that in pediatric practice the number of severe forms and unfavorable outcomes may change in the near future, especially due to the difficulty of diagnosing Kawasaki-like syndrome and the need for a multidisciplinary approach to the treatment of such patients. Currently, the most vulnerable to the new CV are children with severe oncological, neurological and cardiovascular pathology, who have a rapid decompensation of the underlying disease against the background of COVID-19.Цель: выявить клинико-лабораторные и эпидемиологические особенности новой коронавирусной инфекции при оказании специализированной медицинской помощи детям в мегаполисе Российской Федерации. Материалы и методы: 674 случая госпитализации пациентов от рождения до 17 лет включительно с подтвержденным COVID-19 в период с 26 марта по 26 июня 2020 г. в детский многопрофильный стационар СанктПетербурга. Диагностика SARS-COV-2 в мазках из верхних дыхательных путей проводилась методом ПЦР (набор реагентов для выявления РНК коронавируса 2019- nCoV методом ПЦР с гибридизационно-флуоресцентной детекцией «Вектор-ПЦРРВ-2019-nCoV–RG»). Пациентам выполнено 4 (3; 5) повторных исследования в зависимости от диагноза направления, а также длительности реконвалесцентного вирусоносительства. Проведен анализ тяжести течения заболевания, основных клинических проявлений и их взаимосвязи с развитием пневмонии, а также эпидемиологических особенностей COVID-19 у детей. Описана продолжительность стационарного лечения, исходы и потребность в интенсивной терапии. Оценены изменения ряда лабораторных показателей на анализаторах производства США: клинический анализ крови на гематологическом – Coulter UniCel (Beckman Coulter), биохимический анализ крови на биохимическом – Uni Cel DxC (Beckman Coulter), коагулограмма на анализаторе гемостаза (Instrumentation Laboratory). Результаты: в целом, отмечено благоприятное течение COVID-19 у детей. Интенсивная терапия потребовалась лишь в 3,6% случаев с общей летальностью 0,15%, Кавасаки-подобный синдром зафиксирован в 0,3% случаев. У 1/3 пациентов выявлено затяжное вирусовыделение из верхних дыхательных путей. У детей лидировало внутрисемейное заражение от взрослых, школьники составили половину всех случаев госпитализации. Отличительной чертой новой инфекции была неяркая клиническая симптоматика с лихорадкой и катаральными симптомами до 4/5 случаев, желудочно-кишечными симптомами – у каждого третьего пациента. Значимых различий в тяжести заболевания по возрастам выявлено не было. Пневмония, диагностированная в ¾ случаев с помощью компьютерной томографии, осложняла течение в 13,1% случаев. Поражение легких сопровождалось лихорадкой и сухим кашлем, а при более тяжелом течении – десатурацией, болями в грудной клетке, чувством неполноценности вдоха. Выявлены возрастные пики заболеваемости пневмонией: в 4, 9, 12 лет и в возрасте 17 лет максимальный (в 1/3 случаев). Изменения лабораторных показателей были несущественными и быстро обратимыми. Заключение: течение COVID-19 у детей в мегаполисе России сопоставимо с зарубежными данными. Однако, учитывая опыт испанки, не исключено, что в педиатрической практике число тяжелых форм и неблагоприятных исходов может измениться в ближайшем будущем, особенно по причине сложности диагностики Кавасакиподобного синдрома и необходимости мультидисциплинарного подхода к терапии таких пациентов. В настоящее время наиболее уязвимыми в отношении нового коронавируса являются дети с тяжелой онкологической, неврологической и сердечно-сосудистой патологией, у которых происходит быстрая декомпенсация основного заболевания на фоне COVID-19