scholarly journals A Versatile New Reagent for Nitrosation under Mild Conditions

2021 ◽  
Author(s):  
Jordan D. Galloway ◽  
Cristian Sarabia ◽  
James C. Fettinger ◽  
Hrant Hratchian ◽  
Ryan Baxter
Keyword(s):  
Room Temperature ◽  
Computational Analysis ◽  
Functional Group ◽  
Nitroso Compounds ◽  
Chemical Reagent ◽  
Experimental Conditions ◽  
X Ray ◽  
Mild Conditions ◽  
Rotational Isomers ◽  
First Time

We report a new chemical reagent for transnitrosation under mild experimental conditions. This new reagent is stable to air and moisture across a broad range of temperatures, and is effective for transnitrosation in multiple solvents. Compared to traditional nitrosation methods, our reagent shows high functional group tolerance for substrates that are susceptible to oxidation or reversible transnitrosation. Several challenging nitroso-compounds are accessed here for the first time, including 15N isotopologues. X-ray data confirms two rotational isomers of the reagent are configurationally stable at room temperature, although only one isomer is effective for transnitrosation. Computational analysis describes the energetics of rotamer interconversion, including interesting geometry-dependent hybridization ef-fects.

scholarly journals A Versatile New Reagent for Nitrosation under Mild Conditions

2021 ◽  
Author(s):  
Jordan D. Galloway ◽  
Cristian Sarabia ◽  
James C. Fettinger ◽  
Hrant Hratchian ◽  
Ryan Baxter
Keyword(s):  
Room Temperature ◽  
Computational Analysis ◽  
Functional Group ◽  
Nitroso Compounds ◽  
Chemical Reagent ◽  
Experimental Conditions ◽  
X Ray ◽  
Mild Conditions ◽  
Rotational Isomers ◽  
First Time

We report a new chemical reagent for transnitrosation under mild experimental conditions. This new reagent is stable to air and moisture across a broad range of temperatures, and is effective for transnitrosation in multiple solvents. Compared to traditional nitrosation methods, our reagent shows high functional group tolerance for substrates that are susceptible to oxidation or reversible transnitrosation. Several challenging nitroso-compounds are accessed here for the first time, including 15N isotopologues. X-ray data confirms two rotational isomers of the reagent are configurationally stable at room temperature, although only one isomer is effective for transnitrosation. Computational analysis describes the energetics of rotamer interconversion, including interesting geometry-dependent hybridization ef-fects.

CsOH and its Lighter Homologues – a Comparison

2014 ◽  
Vol 69 (11-12) ◽  
pp. 1229-1236
Author(s):  
Matthias Wörsching ◽  
Constantin Hoch
Keyword(s):  
Gas Phase ◽  
Room Temperature ◽  
Structure Type ◽  
Alkali Metal Hydroxide ◽  
X Ray ◽  
Raman Spectroscopic ◽  
Cesium Hydroxide ◽  
Free Ion ◽  
The One ◽  
First Time

Abstract Cesium hydroxide, CsOH, was for the first time characterised on the basis of single-crystal data. The structure is isotypic to the one of the room-temperature modification of NaOH and can be derived from the NaCl structure type thus allowing the comparison of all alkali metal hydroxide structures. Raman spectroscopic investigations show the hydroxide anion to behave almost as a free ion as in the gas phase. The X-ray investigations indicate possible H atom positions.

First in-beam application of thallium bromide semiconductor detectors to particle-induced X-ray emission

2019 ◽  
Vol 29 (01n02) ◽  
pp. 53-59
Author(s):  
M. Nogami ◽  
K. Hitomi ◽  
A. Terakawa ◽  
K. Ishii
Keyword(s):  
Room Temperature ◽  
Semiconductor Detectors ◽  
Science Center ◽  
Active Volume ◽  
X Ray ◽  
Thallium Bromide ◽  
Quantum Science ◽  
First Time ◽  
Aomori Prefecture ◽  
Zone Purification

For the first time, particle-induced X-ray emission (PIXE) spectra were obtained using TlBr detectors. The TlBr detector was fabricated from a crystal grown with material purified by the zone purification. Its active volume was 1.5 mm × 1.5 mm × 3.1 mm, and it exhibited an energy resolution of a 6.2 keV full-width at half-maximum (FWHM) for 59.5 keV at room temperature. The detector was installed into a PIXE system at Aomori Prefecture Quantum Science Center. A Pb plate target in the PIXE chamber was irradiated with a 20 MeV proton beam, and X-ray peaks for Pb K[Formula: see text] and K[Formula: see text] were successfully detected by the TlBr detector at room temperature.

scholarly journals Physical Stability and Viscoelastic Properties of Co-Amorphous Ezetimibe/Simvastatin System

2019 ◽  
Vol 12 (1) ◽  
pp. 40 ◽  
Author(s):  
Justyna Knapik-Kowalczuk ◽  
Krzysztof Chmiel ◽  
Karolina Jurkiewicz ◽  
Natália Correia ◽  
Wiesław Sawicki ◽  
...  
Keyword(s):  
Elevated Temperature ◽  
Viscoelastic Properties ◽  
Room Temperature ◽  
Physical Stability ◽  
Ternary Systems ◽  
Storage Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Conditions ◽  
First Time

The purpose of this paper is to examine the physical stability as well as viscoelastic properties of the binary amorphous ezetimibe–simvastatin system. According to our knowledge, this is the first time that such an amorphous composition is prepared and investigated. The tendency toward re-crystallization of the amorphous ezetimibe–simvastatin system, at both standard storage and elevated temperature conditions, have been studied by means of X-ray diffraction (XRD). Our investigations have revealed that simvastatin remarkably improves the physical stability of ezetimibe, despite the fact that it works as a plasticizer. Pure amorphous ezetimibe, when stored at room temperature, begins to re-crystallize after 14 days after amorphization. On the other hand, the ezetimibe-simvastatin binary mixture (at the same storage conditions) is physically stable for at least 1 year. However, the devitrification of the binary amorphous composition was observed at elevated temperature conditions (T = 373 K). Therefore, we used a third compound to hinder the re-crystallization. Finally, both the physical stability as well as viscoelastic properties of the ternary systems containing different concentrations of the latter component have been thoroughly investigated.

Ce3+ self-doped CeOx/FeOCl: an efficient Fenton catalyst for phenol degradation under mild conditions

2019 ◽  
Vol 48 (10) ◽  
pp. 3476-3485 ◽  
Author(s):  
Jian Zhang ◽  
Mengxue Yang ◽  
Ye Lian ◽  
Mingliang Zhong ◽  
Jingquan Sha ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Room Temperature ◽  
Phenol Degradation ◽  
Natural Light ◽  
Neutral Solution ◽  
Mild Conditions ◽  
Fenton Catalyst ◽  
First Time

Herein, a novel Ce3+ self-doped CeOx/FeOCl composite was successfully prepared by a facile method for the first time, which showed remarkable catalytic activity as a Fenton catalyst in the degradation of phenol under the conditions of a neutral solution, room temperature and natural light.

scholarly journals Quasi-hydrostatic equation of state of silicon up to 1 megabar at ambient temperature

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Simone Anzellini ◽  
Michael T. Wharmby ◽  
Francesca Miozzi ◽  
Annette Kleppe ◽  
Dominik Daisenberger ◽  
...  
Keyword(s):  
Equation Of State ◽  
Room Temperature ◽  
Uniaxial Stress ◽  
Sample Volume ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
X Ray ◽  
Pressure Medium ◽  
Diamond Anvil ◽  
Isothermal Equation

Abstract The isothermal equation of state of silicon has been determined by synchrotron x-ray diffraction experiments up to 105.2 GPa at room temperature using diamond anvil cells. A He-pressure medium was used to minimize the effect of uniaxial stress on the sample volume and ruby, gold and tungsten pressure gauges were used. Seven different phases of silicon have been observed along the experimental conditions covered in the present study.

Facile Synthesis of 4,5-Dihydro-1,3,4-Thiadiazoles by 1,3-Dipolar Cycloaddition of Thioisomünchnones

2009 ◽  
Vol 62 (4) ◽  
pp. 356 ◽  
Author(s):  
Bárbara Sánchez ◽  
José Luis Bravo ◽  
María Josí Arívalo ◽  
Ignacio López ◽  
Mark E. Light ◽  
...  
Keyword(s):  
Structure Analysis ◽  
Structure Elucidation ◽  
Room Temperature ◽  
Dipolar Cycloaddition ◽  
Two Dimensional ◽  
Facile Synthesis ◽  
X Ray ◽  
Mild Conditions ◽  
Nmr Techniques

The present paper summarizes a straightforward synthesis of 4,5-dihydro-1,3,4-thiadiazoles by the 1,3-dipolar cycloaddition of thioisomünchnones. These reactions have been carried out in dichloromethane and are essentially complete within 60 min at room temperature. Under such mild conditions the asymmetric version has been explored as well. Unequivocal structure elucidation has been accomplished by means of one- and two-dimensional NMR techniques as well as X-ray structure analysis.

Temperature dependence of the AV3O7 (A = Ca, Sr) structure

2007 ◽  
Vol 63 (6) ◽  
pp. 836-842 ◽  
Author(s):  
Sebastian Prinz ◽  
Karine M. Sparta ◽  
Georg Roth
Keyword(s):  
Single Crystal ◽  
Temperature Dependence ◽  
Crystal Structures ◽  
Room Temperature ◽  
X Ray Diffraction ◽  
X Ray ◽  
Space Groups ◽  
Temperature Ranges ◽  
First Time

The V4+ (spin ½) oxovanadates AV3O7 (A = Ca, Sr) were synthesized and studied by means of single-crystal X-ray diffraction. The room-temperature structures of both compounds are orthorhombic and their respective space groups are Pnma and Pmmn. The previously assumed structure of SrV3O7 has been revised and the temperature dependence of both crystal structures in the temperature ranges 297–100 K and 315–100 K, respectively, is discussed for the first time.

Synthesis of O-Aroyl-N,N-dimethylhydroxylamines through Hypervalent Iodine-Mediated Amination of Carboxylic Acids with N,N-Dimethylformamide

Synthesis ◽  
2017 ◽  
Vol 49 (18) ◽  
pp. 4303-4308 ◽  
Author(s):  
Dong Li ◽  
Chuancheng Zhang ◽  
Qiang Yue ◽  
Zhen Xiao ◽  
Xianglan Wang ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Room Temperature ◽  
Functional Group ◽  
Hypervalent Iodine ◽  
Electrophilic Amination ◽  
Mild Conditions

An efficient protocol for the synthesis of O-aroyl-N,N-dimethylhydroxylamines, which are important electrophilic amination reagents, is described. The reaction between carboxylic acids and N,N-dimethylformamide is mediated by hypervalent iodine and occurs under mild conditions at room temperature to give the desired products in good yields. The process shows good functional group compatibility and air and moisture tolerance.

Accuracy in quantitative phase analysis of mixtures with large amorphous contents. The case of stoneware ceramics and bricks

2014 ◽  
Vol 47 (3) ◽  
pp. 835-846 ◽  
Author(s):  
Alessandro F. Gualtieri ◽  
Vincenzo Riva ◽  
Andrea Bresciani ◽  
Stefano Maretti ◽  
Marco Tamburini ◽  
...  
Keyword(s):  
Phase Analysis ◽  
Internal Standard ◽  
Quantitative Phase Analysis ◽  
Experimental Conditions ◽  
X Ray ◽  
Quantitative Phase ◽  
Factor Method ◽  
Counting Statistics ◽  
First Time ◽  
X Ray Absorption

For the first time, this work inspects the accuracy of quantitative phase analysis of both crystalline and amorphous components of stoneware tiles and bricks. A number of variables were considered: the nature of the internal standard, experimental conditions and counting statistics. The so-calledG-factor method has also been applied. The results of the X-ray powder diffraction analysis have been compared with the results obtained with optical microscopy and image analysis. Only the mixtures spiked with corundum and silicon yielded accurate weight estimates of the amorphous fraction, whereas the use of highly X-ray absorbing internal standards (such as fluorite, rutile and zincite) resulted in gross underestimations. In fact, microabsorption effects are found to drastically reduce the accuracy of the results when standards with linear X-ray absorption coefficients higher than 100 cm−1are employed. It was found that very low counting statistics reduced the calculated amorphous fractions in both bricks and stoneware tiles owing to partial masking of the major peak of the internal standard, namely corundum. The application of theG-factor method to the systems investigated was also evaluated. The results are poorer than those obtained using the internal standard.

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