The Experts below are selected from a list of 222 Experts worldwide ranked by ideXlab platform
S.w. Shah - One of the best experts on this subject based on the ideXlab platform.
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Syntheses and thermoanalytical studies of some schiff base polymers derived from 5,5′-methylene bis(2-hydroxyacetophenone)
European Polymer Journal, 1998Co-Authors: Muhammad Yar Khuhawar, A.h. Channar, S.w. ShahAbstract:Abstract Six Schiff base polymers poly 5,5′-methylenebis(2-hydroxyacetophenone)1,2-ethylenediimine (PHAen), poly[5,5′-methylenebis(2-hydroxyacetophenone)1,2-propylenediamine] (PHAPn), poly[5,5′-methylenebis (2-hydroxyacetophenone) 1,3-propyledenediamine] (PHAPR), poly[5,5′-methylenebis(2-hydroxyacetophenone) dl-stilbenediimine] (dl-PHAS), poly[5,5′-methylenebis(2-hydroxyacetophenone)-meso-stilbenediamine] (meso-PHAS), and poly[5,5′-methylenebis(2-hydroxyacetophenone)azine] (PHAH) have been prepared by polycondensation of 5,5′-methylenebis(2-hydroxyacetophenone (MHA) with Ethylenediamine, dl-stilbenediamine meso-stilbenediamine or hydrazine. Each of the polymers has been characterized by elemental microanalysis, infrared and ultraviolet spectroscopy. Their thermogravimetry (TG) and differential thermal analysis (DTA) have been recorded and evaluated. The reduced viscosity of the polymers measured in tetrahydrofuran (THF), dimethylformamide (DMF) and dimethyl sulphoxide (DMSO) was found within 0.202–0.505 dl/g.
J.-r. Hamon - One of the best experts on this subject based on the ideXlab platform.
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A facile access to new diazepines derivatives: Spectral characterization and crystal structures of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine
Journal of Molecular Structure, 2016Co-Authors: G. Ahumada, D. Carrillo, C. Manzur, M. Fuentealba, T. Roisnel, J.-r. HamonAbstract:The one-pot double condensation reaction of 2-thenoyltrifluoroacetone (2-TTA) with ethylendiamine or o-phenylenediamine, in a 2:1 stoichiometric molar ratio, leads to the formation of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine 2 and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine 3, that were isolated in 56 and 53% yields, respectively. The bis(trifluoroacetamide)ethylene derivative 1 was also isolated in 32% yield as a side-product in the reaction of 2-TTA and Ethylenediamine. Compounds 1–3 were fully characterized by elemental analysis, FT-IR and multinuclear (1H, 13C and 19F) NMR spectroscopy. In addition, their molecular identities and geometries have been authenticated by single-crystal X-ray diffraction analysis. The spectroscopic and structural data confirm that the 1,4-diazepine 2 and the 1,5-benzodiazepine 3 exist in the imine-enamine and diimine tautomeric forms, respectively, both in solution and in the solid-state. © 2016 Elsevier B.V.
Hamon J.-r. - One of the best experts on this subject based on the ideXlab platform.
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A facile access to new diazepines derivatives: Spectral characterization and crystal structures of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine
'Elsevier BV', 2016Co-Authors: Ahumada G., Carrillo D., Manzur C., Fuentealba M., Roisnel T., Hamon J.-r.Abstract:International audienceThe one-pot double condensation reaction of 2-thenoyltrifluoroacetone (2-TTA) with ethylendiamine or o-phenylenediamine, in a 2:1 stoichiometric molar ratio, leads to the formation of 7-(thiophene-2-yl)-5-(trifluoromethyl)-2,3-dihydro-1H-1,4-diazepine 2 and 2-thiophene-4-trifluoromethyl-1,5-benzodiazepine 3, that were isolated in 56 and 53% yields, respectively. The bis(trifluoroacetamide)ethylene derivative 1 was also isolated in 32% yield as a side-product in the reaction of 2-TTA and Ethylenediamine. Compounds 1–3 were fully characterized by elemental analysis, FT-IR and multinuclear (1H, 13C and 19F) NMR spectroscopy. In addition, their molecular identities and geometries have been authenticated by single-crystal X-ray diffraction analysis. The spectroscopic and structural data confirm that the 1,4-diazepine 2 and the 1,5-benzodiazepine 3 exist in the imine-enamine and diimine tautomeric forms, respectively, both in solution and in the solid-state. © 2016 Elsevier B.V
S. C. Mojumdar - One of the best experts on this subject based on the ideXlab platform.
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Co(II)-exchanged montmorillonite with Ethylenediamine, trimethyl- and tetramethyl-Ethylenediamine and their thermal decomposition
Journal of Thermal Analysis and Calorimetry, 2011Co-Authors: S. Šnircová, E. Jóna, R. Janík, Ľ. Lajdová, S. Lendvayová, M. Loduhová, V. Šutinská, R. Durný, P. Lizák, S. C. MojumdarAbstract:The influence of different steric properties of Ethylenediamine (EDA), trimEthylenediamine (TrMeEDA) and tetraEthylenediamine (TeMeEDA) on the type of interactions with Co(II)-exchanged montmorillonite and thermal decomposition of these materials were studied. The results of X-ray diffraction (XRD), thermogravimetry (TG), derivative thermogravimetry (DTG) and spectral analysis shows that the studied Ethylenediamines are intercalated into the interlayer space of montmorillonite. Thermal decomposition at 20–500 °C of studied samples with EDA proceeds in three steps (the release of chemosorbed amines, coordinated EDA and dehydroxylation) while the sample with TrMeEDA and TeMeEDA in five steps (also release the protonated forms). The effect of different steric properties of individual diamines is evident.
Muhammad Yar Khuhawar - One of the best experts on this subject based on the ideXlab platform.
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Syntheses and thermoanalytical studies of some schiff base polymers derived from 5,5′-methylene bis(2-hydroxyacetophenone)
European Polymer Journal, 1998Co-Authors: Muhammad Yar Khuhawar, A.h. Channar, S.w. ShahAbstract:Abstract Six Schiff base polymers poly 5,5′-methylenebis(2-hydroxyacetophenone)1,2-ethylenediimine (PHAen), poly[5,5′-methylenebis(2-hydroxyacetophenone)1,2-propylenediamine] (PHAPn), poly[5,5′-methylenebis (2-hydroxyacetophenone) 1,3-propyledenediamine] (PHAPR), poly[5,5′-methylenebis(2-hydroxyacetophenone) dl-stilbenediimine] (dl-PHAS), poly[5,5′-methylenebis(2-hydroxyacetophenone)-meso-stilbenediamine] (meso-PHAS), and poly[5,5′-methylenebis(2-hydroxyacetophenone)azine] (PHAH) have been prepared by polycondensation of 5,5′-methylenebis(2-hydroxyacetophenone (MHA) with Ethylenediamine, dl-stilbenediamine meso-stilbenediamine or hydrazine. Each of the polymers has been characterized by elemental microanalysis, infrared and ultraviolet spectroscopy. Their thermogravimetry (TG) and differential thermal analysis (DTA) have been recorded and evaluated. The reduced viscosity of the polymers measured in tetrahydrofuran (THF), dimethylformamide (DMF) and dimethyl sulphoxide (DMSO) was found within 0.202–0.505 dl/g.
