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Ahmadi-varzaneh - One of the best experts on this subject based on the ideXlab platform.
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One‐Pot Synthesis of 1,2,4,5‐Tetrahydro‐2,4‐dioxobenzo[b][1,4]diazepine and Malonamide Derivatives Using Multi‐Component Reactions.
ChemInform, 2015Co-Authors: Abbas Rahmati, Samaneh Ahmadi, Ahmadi-varzanehAbstract:Multicomponent reaction of o-phenylenediamine with arylidene malonitriles, isocyanides, and Meldrum′s acid provides diazepines (V) whereas 1,2-diamines with electron-withdrawing substituent as well as p-phenylenediamine give Malonamide derivatives.
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One-pot synthesis of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine and Malonamide derivatives using multi-component reactions
Tetrahedron, 2014Co-Authors: Abbas Rahmati, Samaneh Ahmadi, Ahmadi-varzanehAbstract:Abstract In this work, a new series of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine and Malonamide derivatives have been synthesized using an aromatic 1,2-diamine, Meldrum's acid, an isocyanide, and an arylidene malononitrile (or an aldehyde and malononitrile instead of an arylidene malononitrile) in CH2Cl2 at ambient temperature. Synthesis of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine proceeded via four- and five-component reactions; while the synthesis of Malonamide derivatives was performed using five- and six-component reactions. In addition, a new series of the Malonamide derivatives have been prepared using an aldehyde, malononitrile, Meldrum's acid, an isocyanide, and two molecules of 1,4-diamine via a six-component reaction. These procedures provide alternative methods to the synthesis of a new series of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine and Malonamide derivatives.
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Synthesis of novel series of Malonamides derivatives via a five-component reaction.
Molecular diversity, 2013Co-Authors: Abbas Rahmati, Tahmineh Kenarkoohi, Ahmadi-varzanehAbstract:A one-pot, five-component condensation reaction of isocyanide, Meldrum’s acid, arylidene malononitrile, and two amine molecules in \(\mathrm{CH}_{2}\mathrm{Cl}_{2}\) at ambient temperature to give Malonamide derivatives is described.
Aurora E. Clark - One of the best experts on this subject based on the ideXlab platform.
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Amphiphile Organization in Organic Solutions: An Alternative Explanation for Small-Angle X-ray Scattering Features in Malonamide/Alkane Mixtures.
The journal of physical chemistry. B, 2020Co-Authors: Michael J. Servis, Marek Piechowicz, Ilya A. Shkrob, L. Soderholm, Aurora E. ClarkAbstract:The role of different intermolecular interactions in the aggregation of amphiphiles in an organic solvent is studied for systems of relevance to liquid-liquid extraction (LLE), a chemical process used to selectively recover metals from complex mixtures. Of specific interest is the role, or lack thereof, of hydrogen bonding, which is often assumed to be a main driver of the organic phase structural organization that has been linked to separation efficacy. Toward that end, a series of Malonamide extractants in n-dodecane have been studied in the absence of any extracted aqueous solutes, including water. The series of extractants includes N,N'-dimethyl-N,N'-dibutyltetradecylMalonamide (DMDBTDMA), two of its homologs, and N,N'-dimethyl-N,N'-dioctylhexylethoxyMalonamide (DMDOHEMA). This simplified model LLE system enables systematic investigation of the role of dipole-dipole and alkyl tail steric interactions in amphiphile aggregation. Small-angle X-ray scattering (SAXS) profiles computed from molecular dynamics trajectories are in good agreement with experimental SAXS data. Molecular dynamics simulations show that Malonamide aggregation results from dipole-driven self-association and lacks characteristic aggregate sizes. Mid-q correlation peaks in the SAXS profiles emerge at high concentration for each Malonamide. In those densely packed solutions, the correlation peaks are observed to result from alkyl tail-induced spacing between electron-rich polar head groups, with peak positions determined by the different alkyl tail lengths present in the Malonamide molecule. This explanation of the SAXS correlation peaks contrasts with the prevailing literature, which attributes mesoscale features observed in small-angle scattering to the formation of microemulsions. Instead, this work finds that these features are present in the absence of water or any reverse micellar organization of the Malonamides. As such, molecular-scale Malonamide self-association and packing, rather than microemulsion-based colloidal-scale descriptions, is a more appropriate framework for these LLE systems.
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amphiphile organization in organic solutions an alternative explanation for small angle x ray scattering features in Malonamide alkane mixtures
Journal of Physical Chemistry B, 2020Co-Authors: Michael J. Servis, Marek Piechowicz, Ilya A. Shkrob, L. Soderholm, Aurora E. ClarkAbstract:The role of different intermolecular interactions in the aggregation of amphiphiles in an organic solvent is studied for systems of relevance to liquid-liquid extraction (LLE), a chemical process used to selectively recover metals from complex mixtures. Of specific interest is the role, or lack thereof, of hydrogen bonding, which is often assumed to be a main driver of the organic phase structural organization that has been linked to separation efficacy. Toward that end, a series of Malonamide extractants in n-dodecane have been studied in the absence of any extracted aqueous solutes, including water. The series of extractants includes N,N'-dimethyl-N,N'-dibutyltetradecylMalonamide (DMDBTDMA), two of its homologs, and N,N'-dimethyl-N,N'-dioctylhexylethoxyMalonamide (DMDOHEMA). This simplified model LLE system enables systematic investigation of the role of dipole-dipole and alkyl tail steric interactions in amphiphile aggregation. Small-angle X-ray scattering (SAXS) profiles computed from molecular dynamics trajectories are in good agreement with experimental SAXS data. Molecular dynamics simulations show that Malonamide aggregation results from dipole-driven self-association and lacks characteristic aggregate sizes. Mid-q correlation peaks in the SAXS profiles emerge at high concentration for each Malonamide. In those densely packed solutions, the correlation peaks are observed to result from alkyl tail-induced spacing between electron-rich polar head groups, with peak positions determined by the different alkyl tail lengths present in the Malonamide molecule. This explanation of the SAXS correlation peaks contrasts with the prevailing literature, which attributes mesoscale features observed in small-angle scattering to the formation of microemulsions. Instead, this work finds that these features are present in the absence of water or any reverse micellar organization of the Malonamides. As such, molecular-scale Malonamide self-association and packing, rather than microemulsion-based colloidal-scale descriptions, is a more appropriate framework for these LLE systems.
Ana Paula Paiva - One of the best experts on this subject based on the ideXlab platform.
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Iron(III) extraction from chloride media by N,N'-tetrasubstituted Malonamides: An interfacial study
Journal of colloid and interface science, 2013Co-Authors: M. Soledade C.s. Santos, Ana Paula PaivaAbstract:Abstract The interfacial behaviour of two N,N′-tetrasubstituted Malonamides, N,N′-dimethyl-N,N′-diphenyl Malonamide (DMDPHMA) and N,N′-dimethyl-N,N′-dicyclohexylMalonamide (DMDCHMA), in the liquid–liquid (L/L) extraction of iron(III) from hydrochloric acid solutions, was studied. The experimental results obtained validate the absence of third phases for these systems. The equilibrium adsorption constants and surface excess concentrations, estimated by the Szyszkowski model, explain the experimental extraction efficiency patterns for both Malonamides in the two diluents tested, 1,2-dichloroethane (1,2-DCE) and toluene. A solvation type mechanism is in accordance with all the results obtained, accounting for the structural and diluent effects observed.
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The Solvent Extraction of Iron(III) from Chloride Solutions by N,N′‐Tetrasubstituted Malonamides: Structure‐Activity Relationships
Solvent Extraction and Ion Exchange, 2007Co-Authors: Maria Clara Costa, I. Pêczek, Z. Sadowski, S. Natu, Ana Paula PaivaAbstract:Abstract The extraction of iron(III) from chloride solutions has been investigated using N,N′‐dimethyl‐N,N′‐diphenylhexylMalonamide (DMDΦ(H)MA), N,N′‐ dimethyl‐N,N′‐diphenyldodecylMalonamide (DMDΦ(D)MA), N,N′‐dimethyl‐N,N′‐dicyclohexylMalonamide (DMDCMA) and N,N′‐dimethyl‐N,N′‐dihexylMalonamide (DMDHMA). The main aim of this work was to investigate whether there is a relation between the chemical structure of Malonamides and their iron(III) extraction behavior, and to try to understand the dependence of the metal extraction mechanism on the structural characteristics of the Malonamides. The introduction of an alkyl chain on the central carbon atom of N,N′‐dimethyl‐N,N′‐diphenyl skeleton Malonamides increases the affinity of the organic derivatives for iron(III) at lower hydrochloric acid concentrations: the longer the alkyl chain, the lower the acidity of half of the extraction of iron(III) is. A similar behavior has been observed both for DMDCMA and DMDHMA when N,N′‐dimethyl‐N,N′‐diphenylMalonamide (DMDΦ...
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Application of N,N′-tetrasubstituted Malonamides to the recovery of iron(III) from chloride solutions
Hydrometallurgy, 2005Co-Authors: Ana Paula Paiva, Maria Clara CostaAbstract:Abstract In this work, three N , N ′-tetrasubstituted Malonamides, namely N , N ′-dimethyl- N , N ′-dibutylMalonamide (DMDBMA), N , N ′-dimethyl- N , N ′-diphenylMalonamide (DMDPHMA) and N , N ′-dimethyl- N , N ′-diphenyltetradecylMalonamide (DMDPHTDMA), are presented as suitable agents for use in a solvent extraction approach to efficiently and selectively remove Fe(III) from concentrated chloride solutions. The efficiency found for Fe(III) extraction from 4 M and higher concentrated hydrochloric acid solutions, the ease of Fe(III) stripping from the loaded solvents with distilled water, the selectivity towards Fe(III) over several other metal ions and the promising results achieved in successive extraction-stripping tests are relevant features that justify further research in view of a practical application. Evidences of the occurrence of different Fe(III) extraction reactions, depending on the Malonamide structure, have also been collected and herein summarized.
Abbas Rahmati - One of the best experts on this subject based on the ideXlab platform.
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One‐Pot Synthesis of 1,2,4,5‐Tetrahydro‐2,4‐dioxobenzo[b][1,4]diazepine and Malonamide Derivatives Using Multi‐Component Reactions.
ChemInform, 2015Co-Authors: Abbas Rahmati, Samaneh Ahmadi, Ahmadi-varzanehAbstract:Multicomponent reaction of o-phenylenediamine with arylidene malonitriles, isocyanides, and Meldrum′s acid provides diazepines (V) whereas 1,2-diamines with electron-withdrawing substituent as well as p-phenylenediamine give Malonamide derivatives.
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one pot synthesis of 1 2 4 5 tetrahydro 2 4 dioxobenzo b 1 4 diazepine and Malonamide derivatives using multi component reactions
ChemInform, 2015Co-Authors: Abbas Rahmati, Samaneh Ahmadi, Mahdi AhmadivarzanehAbstract:Multicomponent reaction of o-phenylenediamine with arylidene malonitriles, isocyanides, and Meldrum′s acid provides diazepines (V) whereas 1,2-diamines with electron-withdrawing substituent as well as p-phenylenediamine give Malonamide derivatives.
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One-pot synthesis of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine and Malonamide derivatives using multi-component reactions
Tetrahedron, 2014Co-Authors: Abbas Rahmati, Samaneh Ahmadi, Ahmadi-varzanehAbstract:Abstract In this work, a new series of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine and Malonamide derivatives have been synthesized using an aromatic 1,2-diamine, Meldrum's acid, an isocyanide, and an arylidene malononitrile (or an aldehyde and malononitrile instead of an arylidene malononitrile) in CH2Cl2 at ambient temperature. Synthesis of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine proceeded via four- and five-component reactions; while the synthesis of Malonamide derivatives was performed using five- and six-component reactions. In addition, a new series of the Malonamide derivatives have been prepared using an aldehyde, malononitrile, Meldrum's acid, an isocyanide, and two molecules of 1,4-diamine via a six-component reaction. These procedures provide alternative methods to the synthesis of a new series of 1,2,4,5-tetrahydro-2,4-dioxobenzo[b][1,4]diazepine and Malonamide derivatives.
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Synthesis of novel series of Malonamides derivatives via a five-component reaction.
Molecular diversity, 2013Co-Authors: Abbas Rahmati, Tahmineh Kenarkoohi, Ahmadi-varzanehAbstract:A one-pot, five-component condensation reaction of isocyanide, Meldrum’s acid, arylidene malononitrile, and two amine molecules in \(\mathrm{CH}_{2}\mathrm{Cl}_{2}\) at ambient temperature to give Malonamide derivatives is described.
Laurence Berthon - One of the best experts on this subject based on the ideXlab platform.
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liquid liquid extraction of acids and water by a Malonamide i anion specific effects on the polar core microstructure of the aggregated Malonamide
Solvent Extraction and Ion Exchange, 2014Co-Authors: Christophe Dejugnat, Laurence Berthon, Veronique Dubois, Yannick Meridiano, Sandrine Dourdain, Stephane Pelletrostaing, Dominique Guillaumont, Thomas ZembAbstract:In a solvent extraction process, the compositions of the phases in thermodynamic equilibrium (described as a Winsor-II regime) must be determined to obtain the extraction isotherms of ions as well as co-extracted water. By comparing the extractions of a series of acids by the Malonamide DMDOHEMA (N,N’-dimethyl-N,N’-dioctyl hexylethoxy Malonamide) in n-heptane, the specific anion effects regarding third phase formation and the strength of the acid-extractant interaction were investigated. It is shown that third phase formation is driven by hydration enthalpy of acid, while the polar core microstructure is controlled by the pKa of the acids. Upon acid extraction, the promotion of third phase formation follows the series H2SO4 ≈ H3PO4 ≈ HClO4 > HNO3 > HCl > HCOOH, which correlates to hydration enthalpy of acid in the case of monoacids. The combination of IR spectroscopy and DFT calculations revealed two different modes of acid extraction, either by hydrogen bonding (extraction of non-dissociated acid: HA) or...
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Experimental and theoretical study of the degradation of Malonamide extractant molecules under ionizing radiation
RSC Advances, 2012Co-Authors: S. Le Caër, Laurence Berthon, Dominique Guillaumont, Nicole Zorz, G. Vigneron, Philippe MoisyAbstract:The behavior of three Malonamides diluted in octane and submitted to ionizing radiation has been studied by means of in situ infrared spectroscopy, electrospray ionization mass spectrometry and quantum chemistry calculations. The major channel at low dose for a Malonamide with ethyl groups on the nitrogen atoms and no substituent on the central carbon atom arises from the addition of an octyl group from the solvent. Adding alkyl chains on the nitrogen atoms and/or an alkyl chain on the central carbon atom weakens the central C–C bond which is then preferentially cleaved upon irradiation. The other bond cleavages (both C–N and C–H cleavages) are then detected when increasing the dose.
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relation between the hydrophile hydrophobe ratio of Malonamide extractants and the stability of the organic phase investigation at high extractant concentrations
Physical Chemistry Chemical Physics, 2007Co-Authors: Pierre Bauduin, Laurence Berthon, Fabienne Testard, Thomas ZembAbstract:In the present paper, it is shown that in Malonamide extractant/dodecane mixtures, change in the shape of the extractant aggregate may promote phase demixion. This phenomenon is known as the 3rd phase formation in extractant systems. The shape of the aggregates is dictated by the length of the alkyl chains stabilizing the reverse microemulsion by steric repulsion. Small angle scattering experiments are used to investigate the aggregation states of diamide extractant molecules, namely N,N'dimethyl-N,N'dibutyl-tetradecyl Malonamide (DMDBTDMA) and N,N'dimethyl-N,N'dibutyl-pentyl Malonamide (DMDBPMA), in dodecane. The results are described in a consistent way by the packing parameter concept and by expressing steric repulsion versus Van der Waals inter-aggregate interactions, both curvature dependants. Non-monotonous change in the extractant Critical Micellar Concentration (CMC) as a function of the extractant alkyl chain length is rationalized by comparing Van der Waals attraction between the alkyl chains of both the extractant and the solvent.
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Relation between the hydrophile/hydrophobe ratio of Malonamide extractants and the stability of the organic phase: investigation at high extractant concentrations
Physical chemistry chemical physics : PCCP, 2007Co-Authors: P. Bauduin, Laurence Berthon, Fabienne Testard, Thomas ZembAbstract:In the present paper, it is shown that in Malonamide extractant/dodecane mixtures, change in the shape of the extractant aggregate may promote phase demixion. This phenomenon is known as the 3rd phase formation in extractant systems. The shape of the aggregates is dictated by the length of the alkyl chains stabilizing the reverse microemulsion by steric repulsion. Small angle scattering experiments are used to investigate the aggregation states of diamide extractant molecules, namely N,N'dimethyl-N,N'dibutyl-tetradecyl Malonamide (DMDBTDMA) and N,N'dimethyl-N,N'dibutyl-pentyl Malonamide (DMDBPMA), in dodecane. The results are described in a consistent way by the packing parameter concept and by expressing steric repulsion versus Van der Waals inter-aggregate interactions, both curvature dependants. Non-monotonous change in the extractant Critical Micellar Concentration (CMC) as a function of the extractant alkyl chain length is rationalized by comparing Van der Waals attraction between the alkyl chains of both the extractant and the solvent.
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Photo-oxidation of tertiary amides, main degradation products of large Malonamides
Journal of Photochemistry and Photobiology A: Chemistry, 2004Co-Authors: Franck Delavente, Laurence Berthon, Jean-michel Guillot, Olivier Thomas, Christine NicolAbstract:Abstract Photo-oxidation of large Malonamides N , N ′-dimethyl, N , N ′-dibutyl, tetradecyl Malonamide (DMDBTDMA) and N , N ′-dimethyl, N , N ′-dibutyl, dodecylethoxy Malonamide (DMDBDDEMA)—potential extractants for minor actinides in nuclear fuel reprocessing—leads mainly to the corresponding monoamides: N -butyl N -methyl hexadecanamide (BMHDA) and N -butyl N -methyl dodecyl oxy butanamide (BMDDOBA), respectively. The evolution of these main photoproducts was monitored during the degradation of Malonamide solutions, and also pure monoamide solutions. Irradiation, for 1 h, with a low mercury pressure lamp can destroy BMHDA when diluted to 0.075 mol l −1 in n -dodecane. The two monoamides only differ by an ether bond and the weakness introduced by such a function in an alkyl chain is shown by slightly faster degradation. The relative weakness of BMDDOBA is independent of oxidant addition. Global degradation can be monitored by GC/FID or UV detection at 200 nm.