Apparent carbon–carbon bond cleavage in an epoxide. 2,3,4,5,6-Hexachloro-12-oxopentacyclo[5.4.1.1.8,11.03,10.05,9]tridecane; a minor product from the acid treatment of endrin

1982 ◽  
Vol 60 (4) ◽  
pp. 501-508 ◽  
Author(s):  
John W. ApSimon ◽  
Kazu Yamasaki ◽  
Alain Fruchier ◽  
Alfred S. Chau ◽  
Carol P. Huber
Keyword(s):  
Sulfuric Acid ◽  
Double Bond ◽  
Acid Treatment ◽  
Bond Cleavage ◽  
Single Bond ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nmr Parameters ◽  
Carbon Carbon Bond ◽  
A Minor

The treatment of endrin (1) with sulfuric acid produces ketoendrin 2 and from 6 to 8% of another product that we show to be 2,3,4,4,5,6-hexachloro-12-oxapentacyclo[5.4.1.1.8,11.03,10.05,9]tridecane 3, based initially on spectral evidence and confirmed by a single crystal X-ray diffraction study. The formation of 3 involves an apparent and unusual carbon–carbon single bond cleavage in an epoxide accompanied by cycloaddition to a proximate carbon–carbon double bond. This transformation probably proceeds by the route outlined in ref. 1. Some of the observed nmr parameters of 3 are discussed in the light of its structure and a comparison is made with the observed spectra for endrin (1).

Structure cristalline et moléculaire d'un composé tricyclique contenant le cycle à dix chaînons dioxo diaza diphosphécine

1992 ◽  
Vol 70 (3) ◽  
pp. 809-816 ◽  
Author(s):  
Brigitte Duthu ◽  
Karim El Abed ◽  
Douraid Houalla ◽  
Robert Wolf ◽  
Joël Jaud
Keyword(s):  
Molecular Structure ◽  
Comparative Analysis ◽  
Double Bond ◽  
Mass Spectroscopy ◽  
Crystal And Molecular Structure ◽  
Accurate Information ◽  
X Ray Diffraction ◽  
X Ray ◽  
Nmr Parameters ◽  
C Nmr

The sulfuration of the tricyclic organophosphorous dimer 2 leads easily to the dithiotricyclic derivative 3, which has been characterized by 31P, 1H, and 13C NMR, elemental analysis, and mass spectroscopy. Its crystal and molecular structure has been established by X-ray diffraction and compared to that of 2, which was previously determined. The comparative analysis of X-ray diffraction and NMR parameters gives accurate information about the molecular structure of both compounds. A numerical value of the anistropy cone of the P=S double bond is proposed. Keywords: phosphecine, NMR, X-ray, tricycle.

ChemInform Abstract: CARBON-CARBON BOND CLEAVAGE IN AN EPOXIDE. A MINOR PRODUCT FROM THE ACID TREATMENT OF ENDRIN

1977 ◽  
Vol 8 (52) ◽  
pp. no-no
Author(s):  
J. W. APSIMON ◽  
K. YAMASAKI ◽  
A. FRUCHIER ◽  
A. S. Y. CHAU
Keyword(s):  
Acid Treatment ◽  
Bond Cleavage ◽  
Carbon Bond ◽  
Carbon Carbon Bond ◽  
A Minor

scholarly journals X-ray and Neutron Study on the Structure of Hydrous SiO2 Glass up to 10 GPa

Minerals ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 84 ◽  
Author(s):  
Satoru Urakawa ◽  
Toru Inoue ◽  
Takanori Hattori ◽  
Asami Sano-Furukawa ◽  
Shinji Kohara ◽  
...  
Keyword(s):  
Oxide Glasses ◽  
Void Space ◽  
X Ray Diffraction ◽  
Amorphous Sio2 ◽  
Sio2 Glass ◽  
X Ray ◽  
X Ray Scattering ◽  
Medium Range ◽  
Two Phases ◽  
A Minor

The structure of hydrous amorphous SiO2 is fundamental in order to investigate the effects of water on the physicochemical properties of oxide glasses and magma. The hydrous SiO2 glass with 13 wt.% D2O was synthesized under high-pressure and high-temperature conditions and its structure was investigated by small angle X-ray scattering, X-ray diffraction, and neutron diffraction experiments at pressures of up to 10 GPa and room temperature. This hydrous glass is separated into two phases: a major phase rich in SiO2 and a minor phase rich in D2O molecules distributed as small domains with dimensions of less than 100 Å. Medium-range order of the hydrous glass shrinks compared to the anhydrous SiO2 glass by disruption of SiO4 linkage due to the formation of Si–OD deuterioxyl, while the response of its structure to pressure is almost the same as that of the anhydrous SiO2 glass. Most of D2O molecules are in the small domains and hardly penetrate into the void space in the ring consisting of SiO4 tetrahedra.

Synthesis, crystal structure and molecular conformation of (±)-1-oxoferruginol and (±)-shonanol

2004 ◽  
Vol 219 (10) ◽  
Author(s):  
Swastik Mondal ◽  
Monika Mukherjee ◽  
Arnab Roy ◽  
Debabrata Mukherjee
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Diffraction Data ◽  
Molecular Conformation ◽  
Membered Ring ◽  
Methyl Groups ◽  
Single Bond ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Structures

Abstract(±)-1-oxoferruginol and (±)-shonanol, two potential intermediates in the synthesis of tricyclic diterpenoid ferruginol, have been prepared and crystal structures of the compounds have been investigated using single-crystal X-ray diffraction data. The methyl groups of the isopropyl moiety in (±)-shonanol are disordered over two positions with occupation factors 0.65(1) and 0.35(1), respectively. Although the chemical structures of two compounds are very similar, a C—C single bond in the terminal six-membered ring of (±)-1-oxoferruginol is replaced by a C=C bond in (±)-shonanol, the quantitative isostructurality index calculations indicate that the structures are not isostructural. Intermolecular O—H…O hydrogen bonds between pairs of molecules in the compounds related by center of inversion lead to characteristic dimers forming R

scholarly journals A study concerning the pretreatment of CNTs and its influence on the performance of NIB/CNTs amorphous catalyst

2006 ◽  
Vol 71 (11) ◽  
pp. 1153-1160 ◽  
Author(s):  
Chang Hu-Yuan ◽  
Feng Li ◽  
Li. Hua ◽  
Bin Zhang
Keyword(s):  
Selective Hydrogenation ◽  
Inductively Coupled Plasma ◽  
Acid Treatment ◽  
Chemical Reduction ◽  
X Ray Diffraction ◽  
Chemical Reduction Method ◽  
X Ray ◽  
Inductively Coupled ◽  
Selective Hydrogenation Of Acetylene ◽  
Transmission Electron

As prepared carbon nanotubes were pretreated with nitric acid (CNTs-HNO3) or ammonia (CNTs-NH3). Fourier transform infrared spectroscopy (FTIR) measurements showed that the surface of the nanotubes was functionalized with carboxylic and hydroxyl functional groups after the acid treatment and that basic groups containing nitrogen, such as N-H and C-N, were introduced to the surface of the nanotubes after the ammonia treatment. X-Ray diffraction analysis implied that the nickel residue in the CNTs was effectively removed by acid treatment. However, the nickel residue was only partially eliminated by ammonia pretreatment. NiB amorphous catalysts supported on CNTs-HNO3 and CNTs-NH3 were prepared by the impregnation-chemical reduction method and characterized by transmission electron microscopy (TEM), as well as inductively coupled plasma (ICP) spectroscopy and studied in the selective hydrogenation of acetylene. TEM measurements showed that a high density NiB particles of about 9 nm were homogeneously dispersed on the CNTs-NH3. However, NiB particles (13-23 nm)with amean size of 16 nm were scattered on the CNTs-HNO3.As a result, the activity and selectivity of NiB/CNTs-NH3 were higher than those of NiB/CNTs-HNO3 in the selective hydrogenation of acetylene.

scholarly journals Pengaruh Suhu dan Konsentrasi terhadap Proses Pemisahan Nikel dari Logam Pengotor Menggunakan Metode Leaching

FLUIDA ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 81-92
Author(s):  
Ade Yanti Nurfaidah ◽  
Dheana Putri Lestari ◽  
Rheisya Talitha Azzahra ◽  
Dian Ratna Suminar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sulfuric Acid ◽  
Atmospheric Pressure ◽  
Operating Temperature ◽  
Acid Leaching ◽  
X Ray Diffraction ◽  
X Ray ◽  
Pressure Acid Leaching ◽  
Scanning Electron

Abstrak Nikel merupakan unsur logam yang penggunaannya sudah dikenal dalam industri, terutama pada pelapisan logam dan paduan. Pengolahan nikel dari bijih nikel laterit (jenis Limonit) menggunakan proses hidrometalurgi Atmospheric Pressure Acid Leaching (APAL) yang dinilai lebih ekonomis karena pemakaian energi dan biaya operasional cukup rendah. Media pelarut yang digunakan berupa larutan asam sulfat (H2SO4). Sebelum dilakukan pengolahan, karakterisasi bijih dilakukan menggunakan X-Ray Diffraction (XRD), X-Ray Flourscence (XRF), dan Scanning Electron Microscopy (SEM). Metode penelitian yang dilakukan yaitu literature review. Hasil review dari beberapa artikel jurnal menunjukkan bahwa kadar nikel yang terkandung pada suatu bijih sekitar 1,42%, 2,94 dan 0,95% serta sisanya adalah pengotor. Kondisi operasi yang tepat akan menghasilkan pemurnian nikel yang cukup tinggi. Parameter kondisi operasi yang dapat memengaruhi proses pemisahan nikel diantaranya suhu operasi yang ditunjukan dengan semakin meningkatnya % ekstraksi nikel seiring dengan kenaikan suhu. Selain suhu operasi, konsentrasi pelarut juga salah satu parameter yang mempengaruhi % ekstraksi karena semakin tinggi ion H+ akan memudahkan proses pelarutan sehingga akan mengikat Nikel Oksida yang terdapat pada bijih. Suhu paling optimal untuk menghasilkan nikel dengan kemurnian tinggi dalam operasi pelindian atmosferik adalah 90°C dan konsentrasi asam sulfat 5 M.  Kata Kunci: Nikel, pelindian, suhu, konsentrasi   Abstract  Nickel is a metal element whose use is well known in industry, especially in metal and alloy plating. The processing of nickel from laterite nickel ore (Limonite type) uses a hydrometallurgical process of Atmospheric Pressure Acid Leaching (APAL) which is considered more economical because energy consumption and operational costs are quite low. The solvent medium used is a solution of sulfuric acid (H2SO4). Prior to processing, ore characterization was carried out using X-Ray Diffraction (XRD), X-Ray Flourscence (XRF), and Scanning Electron Microscopy (SEM). The research method literature review article. The results of reviews from several journal articles show that the nickel content contained in an ore is around 1.42%, 2.94% and 0.95% and the rest is impurity. The right operating conditions will result in relatively high nickel refining. The operating condition parameters that can affect the nickel separation process include the operating temperature which is indicated by the increasing % nickel extraction along with the increase in temperature. In addition to operating temperature, solvent concentration is also one of the parameters that affects the% extraction because the higher the H+ ion will facilitate the dissolving process so that it will bind to the Nickel Oxide contained in the ore. The optimal temperature to produce high-purity nickel in atmospheric leaching operations is 90°C and a sulfuric acid concentration of 5 M. Keywords: Nickel, leaching, temperature, concentration

scholarly journals COMPOSITION, STRUCTURE AND TEXTURAL CHARACTERISTICS OF DOMESTIC ACID ACTIVATED BENTONITE

2014 ◽  
Vol 5 (1) ◽  
Author(s):  
Zоrаn Pеtrоvić ◽  
Pеrо Dugić ◽  
Vојislаv Аlеksić ◽  
Sаbinа Bеgić ◽  
Vlаdаn Мićić ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Low Temperature ◽  
Layered Structure ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Textural Characteristics ◽  
X Ray ◽  
Before And After ◽  
Activated Bentonite ◽  
Composition Structure

Bentonites are aluminosilicate minerals which, due to their porosity, layered structure and composition have a wide application. Structural and textural characteristics of bentonite may be improved by different modification procedures. The aim of this study was to investigate compositional, structural and textural characteristics of domestic bentonite in place Gerzovo, before and after the activation with sulfuric acid. These characteristics were investigated by analytical methods, X-ray diffraction (XRD) and the method of low-temperature nitrogen adsorption (BET). Characteristics of acid-activated bentonite were compared with the characteristics of commercial active clay. The obtained results showed that the activation of bentonite with sulfuric acid leads to a significant improvement in structural and textural characteristics. Using these results it can be assumed that this bentonite will have good adsorption characteristics and can serve as an alternative in comparison with imported commercial aluminosilicate-based adsorbents.

The Structure of Polyisoprenes. II. The Structure of β-Gutta-Percha

1945 ◽  
Vol 18 (2) ◽  
pp. 280-283
Author(s):  
G. A. Jeffrey
Keyword(s):  
Molecular Structure ◽  
Double Bond ◽  
Diffraction Data ◽  
X Ray Diffraction ◽  
Interatomic Distances ◽  
Methyl Group ◽  
X Ray ◽  
Gutta Percha ◽  
Qualitative Estimate

Abstract The x-ray diffraction data at present available from β-gutta-percha are shown to be insufficient to distinguish fine details of molecular structure. Since a qualitative estimate of the intensities on the fibre diagram can be adequately satisfied by a model having normal interatomic distances and valency angles, no evidence exists for the improbable distortion of the methyl group out of the plane of the double bond previously ascribed to the molecule.

scholarly journals Reactions of Dihaloboranes with Electron-Rich 1,4-Bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadienes

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2875
Author(s):  
Li Ma ◽  
Xiaolin Zhang ◽  
Wenbo Ming ◽  
Shengxin Su ◽  
Xiaoyong Chang ◽  
...  
Keyword(s):  
Double Bond ◽  
Nmr Spectroscopy ◽  
Diffraction Analysis ◽  
1H Nmr Spectroscopy ◽  
Variable Temperature ◽  
Organosilicon Compounds ◽  
X Ray Diffraction ◽  
X Ray ◽  
Multinuclear Nmr Spectroscopy ◽  
Bond Character

The reactions of electron-rich organosilicon compounds 1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (1), 2,3,5,6-tetramethyl-1,4-bis(trimethylsilyl)-1,4-diaza-2,5-cyclohexadiene (2), and 1,1′-bis(trimethylsilyl)-1,1′-dihydro-4,4′-bipyridine (12) with B-amino and B-aryl dihaloboranes afforded a series of novel B=N-bond-containing compounds 3–11 and 13. The B=N rotational barriers of 7 (>71.56 kJ/mol), 10 (58.79 kJ/mol), and 13 (58.65 kJ/mol) were determined by variable-temperature 1H-NMR spectroscopy, thus reflecting different degrees of B=N double bond character in the corresponding compounds. In addition, ring external olefin isomers 11 were obtained by a reaction between 2 and DurBBr2. All obtained B=N-containing products were characterized by multinuclear NMR spectroscopy. Compounds 5, 9, 10a, 11, and 13a were also characterized by single-crystal X-ray diffraction analysis.

Sign in / Sign up

Export Citation Format

Share Document