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921.
Massimo Brochetta Tania Borsari Sukdev Bag Dr. Sadhan Jana Siddhartha Maiti Prof. Dr. Alessio Porta Prof. Dr. Daniel B. Werz Prof. Dr. Giuseppe Zanoni Prof. Dr. Debabrata Maiti 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(44):10323-10327
The development of efficient and mild methods for the synthesis of organofluorine compounds is of foremost interest in various fields of chemistry. A direct pyrimidine-based selective meta-C−H perfluoroalkenylation of arenes involving several commercially available perfluoroolefins is described. The synthetic versatility of the protocol is demonstrated by an extensive substrate scope including different benzylsulfonyl, alkylarene and phenylacetic acid scaffolds. The generality of this methodology including the meta-C−H perfluoroalkenylation of Ibuprofen, the facile cleavage of the directing group and gram-scale reactions are presented. 相似文献
922.
Dr. Shang-Fu Yuan Wen-Di Liu Dr. Chun-Yu Liu Dr. Zong-Jie Guan Prof. Dr. Quan-Ming Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(24):e202104445
Surface organic ligands are critical in dictating the structures and properties of atomically precise metal nanoclusters. In contrast to the conventionally used thiolate, phosphine and alkynyl ligands, nitrogen donor ligands have not been used in the protection for well-defined metal nanoclusters until recently. This review focuses on recent developments in atomically precise metal nanoclusters stabilized by different types of nitrogen donor ligands, in which the synthesis, total structure determination and various properties are covered. We hope that this review will provide insights into the rational design of N donor-protected metal nanoclusters in terms of structural and functional modulation. 相似文献
923.
A theoretical and experimental study of the NMR spectra of 4,5,6,7‐tetrafluorobenzazoles with special stress on PCM calculations of chemical shifts 下载免费PDF全文
Ibon Alkorta José Elguero Marta Pérez‐Torralba Concepción López Rosa M. Claramunt 《Magnetic resonance in chemistry : MRC》2015,53(5):353-362
The chemical shifts and several 19F–19F, 13C–19F and 1H–19F spin‐spin coupling constants (SSCSs) of eight 4,5,6,7‐tetraflurobenzazoles (three benzimidazoles, three benzimidazolinones and two indazoles) have been determined. The chemical shifts were discussed using gauge including atomic orbital‐density functional theory calculations taking into account solvent effects (polarizable continuum model) and, for the solid state, hydrogen bonds (clusters up to three molecules). Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
924.
The structural and electronic properties of crystalline nitrates have been investigated within the framework of density functional theory including van der Waals interactions. Pressure behavior of nitrates has been investigated using semiempirical dispersion correction scheme DFT-D. The optimizations of the crystal structures have been done with full relaxation of the atomic positions and lattice parameters under the experimentally determined crystal symmetries. The pressure dependences of geometrical parameters, band gaps, densities of states, charge distributions, overlap populations and atomic charges are computed. The predicted results agree well with the available experimental data. 相似文献
925.
Palladium catalyzed direct C–H arylation of 3-bromoisothiazole-5-carbonitrile with aryl/hetaryl iodides in the presence of AgF gave 13 4-aryl/hetaryl-3-bromoisothiazole-5-carbonitriles. The scope of this arylation was investigated and explanations for the limitations proposed. 3-Bromoisothiazole-5-carboxamide was isolated as a side-product, and its formation was attributed to Ag+-catalyzed hydration of the C-5 nitrile. The analogous phenylation of 3-chloroisothiazole-5-carbonitrile and 3-bromoisothiazole-4-carboxamide gave 3-chloro-4-phenylisothiazole-5-carbonitrile and 3-bromo-5-phenylisothiazole-4-carboxamide in 83 and 64% yields, respectively. 相似文献
926.
927.
Lukas M. Müller-Wirtz Daniel Kiefer Joschua Knauf Maximilian A. Floss Jonas Doneit Beate Wolf Felix Maurer Daniel I. Sessler Thomas Volk Sascha Kreuer Tobias Fink 《Molecules (Basel, Switzerland)》2021,26(9)
High inspired oxygen during mechanical ventilation may influence the exhalation of the previously proposed breath biomarkers pentanal and hexanal, and additionally induce systemic inflammation. We therefore investigated the effect of various concentrations of inspired oxygen on pentanal and hexanal exhalation and serum interleukin concentrations in 30 Sprague Dawley rats mechanically ventilated with 30, 60, or 93% inspired oxygen for 12 h. Pentanal exhalation did not differ as a function of inspired oxygen but increased by an average of 0.4 (95%CI: 0.3; 0.5) ppb per hour, with concentrations doubling from 3.8 (IQR: 2.8; 5.1) ppb at baseline to 7.3 (IQR: 5.0; 10.8) ppb after 12 h. Hexanal exhalation was slightly higher at 93% of inspired oxygen with an average difference of 0.09 (95%CI: 0.002; 0.172) ppb compared to 30%. Serum IL-6 did not differ by inspired oxygen, whereas IL-10 at 60% and 93% of inspired oxygen was greater than with 30%. Both interleukins increased over 12 h of mechanical ventilation at all oxygen concentrations. Mechanical ventilation at high inspired oxygen promotes pulmonary lipid peroxidation and systemic inflammation. However, the response of pentanal and hexanal exhalation varies, with pentanal increasing by mechanical ventilation, whereas hexanal increases by high inspired oxygen concentrations. 相似文献
928.
Aromatic nitroderivatives are compounds of considerable environmental concern, because some of them are phytotoxic (especially the nitrophenols, and particularly 2,4-dinitrophenol), others are mutagenic and potentially carcinogenic (e.g., the nitroderivatives of polycyclic aromatic hydrocarbons, such as 1-nitropyrene), and all of them absorb sunlight as components of the brown carbon. The latter has the potential to affect the climatic feedback of atmospheric aerosols. Most nitroderivatives are secondarily formed in the environment and, among their possible formation processes, photonitration upon irradiation of nitrate or nitrite is an important pathway that has periodically gained considerable attention. However, photonitration triggered by nitrate and nitrite is a very complex process, because the two ionic species under irradiation produce a wide range of nitrating agents (such as •NO2, HNO2, HOONO, and H2OONO+), which are affected by pH and the presence of organic compounds and, in turn, deeply affect the nitration of aromatic precursors. Moreover, aromatic substrates can highly differ in their reactivity towards the various photogenerated species, thereby providing different behaviours towards photonitration. Despite the high complexity, it is possible to rationalise the different photonitration pathways in a coherent framework. In this context, this review paper has the goal of providing the reader with a guide on what to expect from the photonitration process under different conditions, how to study it, and how to determine which pathway(s) are prevailing in the formation of the observed nitroderivatives. 相似文献
929.
Dr. Liang Bao Qinyu Bao Dr. Huaiwei Zhang Prof. Dr. Yongjun Yuan 《Chemphyschem》2021,22(21):2168-2171
A feasible tuning method for oxygen vacancies was realized by annealing under 3 atm H2 with (001)-exposed TiO2 nanosheets. The colored TiO2 sample exhibits an excellent N2 photo-fixation rate owing to the abundant oxygen vacancies (OVs) thus demonstrating that annealing with high pressure H2 is exceedingly efficient for tuning surface OVs. 相似文献
930.
Ming-Tsz Chen Yu-Yang Chen Guan-Lin Li Kai-Wen Chou Ching-Han Hu Guo-Cyuan Huang Chi-Tien Chen 《应用有机金属化学》2020,34(4):e5464
This paper describes the effect of solvent-induced synthetic routes of aluminium pendant oxazoline-amido-phenolate complexes. Treatment of ligand precursor L with AlMe3 in a 1:1 ratio in diethyl ether yielded the four-coordinated complex (LAlMe)2. Reaction of ligand precursor L with AlMe3 in a 1:2 ratio in hexane generated the four-coordinated complex L(AlMe2)2. A novel transformation mode occurred from L(AlMe2)2 to (LAlMe)2 when using diethyl ether or tetrahydrofuran as solvent. A density functional theory computational study also supports a plausible mechanism. All results were supported by spectroscopic data and in agreement with single-crystal X-ray diffraction structural analysis. 相似文献