ChemInform Abstract: PHOTOCATALYTIC SYSTEMS. PART XIX. PHOTO- AND THERMOREDOX REACTIONS OF CHROMIUM(VI) COMPOUNDS. PART IV. FORMATION OF FREE RADICALS IN THE PHOTOCHEMICAL OXIDATIONS OF ALCOHOLS BY CHROMIUM(VI) IN GLACIAL ACETIC ACID

The synthesis of 1H-3-aryl-7-ethoxycarbonyl-6-methyl-pyrazolo[5,1-c][1,2,4]triazoles (2) was carried out by cyclization of 1H-5-arylidenehydrazino-4-ethoxycarbonyl-3-methyl-pyrazoles (1) in the presence of bromine using glacial acetic acid as solvent and sodium acetate as base. The new nine obtained compounds were characterized by IR and NMR spectroscopy and mass spectrometry.

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Coordination state of cobalt(II) ions in solution and on a sulphonated organic polymer

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19792330 ◽

1979 ◽

Vol 44 (8) ◽

pp. 2330-2337 ◽

Cited By ~ 1

Author(s):

Jindřiška Maternová ◽

Anastas A. Andreev ◽

Dimitrii M. Shopov ◽

Karel Setínek

Keyword(s):

Acetic Acid ◽

Coordination Sphere ◽

Glacial Acetic Acid ◽

Organic Polymer ◽

Octahedral Complex ◽

Coordination State ◽

Tetrahedral Symmetry ◽

Liquid Acid ◽

Homogeneous Phase ◽

Bromide Ion

It was found spectroscopically that cobalt(II) acetate dissolved in glacial acetic acid forms the octahedral complex [Co(OAc)2(HOAc)4] which in the presence of bromide ions gives the octahedral [Co(OAc)Br(HOAc)4] and tetrahedral bromo(acetate)cobalt(II) complexes with the higher number of Br- ions. When attached to an organic polymer cobalt(II) ions are bonded in the form of octahedral [Co(H2O)6]2+ cations which form with acetic acid similar complexes as in homogeneous phase and are able to coordinate one bromide ion. Drying the copolymer possessing octahedral hexaaquocobalt(II) cations leads to tetrahedral aquocomplexes which are solvated by gaseous acetic acid and converted into the acetate complexes with the liquid acid. The latter contain the acid in the inner coordination sphere and have tetrahedral symmetry.

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Nitration of Jharia basin coals, India: a study of structural modifications by XRD and FTIR techniques

International Journal of Coal Science & Technology ◽

10.1007/s40789-021-00422-8 ◽

2021 ◽

Author(s):

Prabal Boral ◽

Atul K. Varma ◽

Sudip Maity

Keyword(s):

Acetic Acid ◽

Nitric Acid ◽

Linear Relationship ◽

Glacial Acetic Acid ◽

Vitrinite Reflectance ◽

Aqueous Media ◽

Interlayer Spacing ◽

Acetic Acid Medium ◽

X Ray ◽

The Media

AbstractFour coal samples from Jharia basin, India are treated with nitric acid in glacial acetic acid and aqueous media to find out the chemical, petrographic and spatial structure of the organic mass by X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) techniques. X-ray parameters of coal like interlayer spacing (d002), crystallite size (Lc), aroamticity (fa), average number of aromatic layers (Nc), and coal rank (I26/I20) have been determined using profile-fitting software. Considerable variation is observed in treated coals in comparison to the demineralized coals. The d002 values of treated coals have increased in both the media showing increase in disordering of organic moieties. A linear relationship has been observed between d002 values with the volatile matter of the coals. Similarly, the d002 values show linear relationship with Cdmf contents for demineralized as well as for the treated coals in both the media. The Lc and Nc values have decreased in treated coals corresponding to demineralized coals. The present study shows that nitration in both the media is capable of removing the aliphatic side chains from the coals and aromaticity (fa) increases with increase in rank and shows a linear relationship with the vitrinite reflectance. The corresponding I26/I20 values are least for treated coals in glacial acetic acid medium followed by raw and then to treated coals in aqueous medium. FTIR studies show that coal arenes of the raw coals are converted into nitro-arenes in structurally modified coals (SMCs) in both the media, the corresponding bands at 1550–1490 and 1355–1315 cm−1 respectively. FTIR study confirms that nitration is the predominant phenomenon, though, oxidation and nitration phenomena takes place simultaneously during treatment with nitric acid to form SMCs. In comparison to raw coals, the SMCs show higher aromaticity and may be easily converted to coal derived products like activated carbon and specialty carbon materials.

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HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

Journal of Chromatographic Science ◽

10.1093/chromsci/bmaa094 ◽

2020 ◽

Author(s):

Xue Yang ◽

Yongling Liu ◽

Tao Chen ◽

Nana Wang ◽

Hongmei Li ◽

...

Keyword(s):

Acetic Acid ◽

Ethyl Acetate ◽

Dimethyl Sulfoxide ◽

Efficient Method ◽

Crude Extract ◽

High Speed ◽

Glacial Acetic Acid ◽

Butyl Alcohol ◽

Preparative Hplc ◽

Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

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