109-55-7Relevant articles and documents
Role of hydrogen-bonded nucleophiles in aromatic nucleophilic substitutions in aprotic solvents. Reactions of halonitrobenzenes with ethylenediamine, 3-dimethylamino-1-propylamine and histamine in toluene
Alvaro, Cecilia E. Silvana,Nudelman, Norma Sbarbati
, p. 880 - 885 (2005)
The kinetics of the reactions between 1-halogeno-2,4-dinitrobenzene (halogen = F, C1) and the amines ethylenediamine (EDA) and 3-dimethylamino-1- propylamine (DMPA) were studied in toluene at 25° ±0.2C under pseudo-first-order conditions using varying amounts of amine. Even with C1 as the nucleofugue (where usually the first step is rate-determining), a third-order-in-amine kinetic law was observed: these results can be interpreted within the 'dimer nucleophile' mechanism where the amine homo-aggregates are better nucleophiles than the amine monomers. To confirm this interpretation, the reaction of 2,4-dinitrofluorobenzene with histamine was studied in the same solvent. Because of the rigid geometry, an intramolecular hydrogen bond is easily established, which prevents the formation of self-aggregates. Consequently, the plot of kA vs. [histamine] is a straight line, as expected for a classical mechanism of base-catalysed decomposition of the zwitterionic intermediate. All these results are well explained in the frame of the 'dimer nucleophile' mechanism. Copyright
Inter- and intramolecular hydrogen bonds in polyamines: Variable-concentration 1H-NMR studies
Nudelman, Norma Sbarbati,Alvaro, Cecilia E. Silvana
, p. 1067 - 1071 (2011)
Inter- and intramolecular hydrogen bonding play an important role in determining the arrangement, physical properties, and reactivity of a great diversity of structures in chemical and biological systems. Several aromatic nucleophilic substitutions (ANS) in nonpolar aprotic, (non-HBD), solvents recently studied in our laboratory have demonstrated the importance of self-association of amines by hydrogen-bond interactions. In this paper, we describe 1H-NMR studies carried out at room temperature on bi- and polyfunctionalized amines, namely: N-(3-amino-1-propyl)morpholine (3-APMo), histamine, 2-guanidinobenzimidazole (2-GB), 1,2-diaminoethane (EDA), 3-dimethylamino-l-propylamine (DMPA), and 1-(2-aminoethyl)piperidine (2-AEPip). By 1H-NMR measurements of amine solutions at variable concentrations we have shown that 3-APMo, histamine and 2-GB are able to form a six-membered ring by intramolecular hydrogen bonding, while EDA, DMPA, and 2-AEPip form dimers by intermolecular hydrogen bonds. Likewise, variable concentration 1H-NMR studies allowed estimation of the corresponding equilibrium constants for the dimerization. These results are correlated with experimental kinetic results of ANS, confirming hereto the relevance of the "dimer mechanism" in reactions involving these amines. Copyright
A process for preparing N, N - dimethyl - 1, 3 - propanediamines method
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Paragraph 0034-0035; 0037; 00041-0042; 0044; 0049-0050; 0052, (2017/08/26)
The invention relates to a method for preparing N,N-dimethyl-1,3-diaminopropane. The method comprises the steps that acrylonitrile is added into a synthesis kettle, and dimethylamine is added and then removed through decompressing rectifying to prepare N,N-dimethyl amine acrylonitrile; a hydrogenation catalyst is added, liquid ammonia is introduced into the high-pressure kettle, hydrogen is introduced, reacting is performed, settling is performed, then prefractionation is performed, and rectifying is performed to obtain the N,N-dimethyl-1,3-diaminopropane. According to the method for preparing the DMAPA, the technology is simple, improvement of the selectivity is guaranteed, the yield per unit of double slag is greatly decreased, and a large amount of dangerous waste treatment charge is saved; consumption of the raw materials of the acrylonitrile and the dimethylamine is reduced, the raw material consumption cost of a DMAPA synthesis device is saved, that is, the production cost is saved, and the enterprise benefits are increased.
Applications of dynamic combinatorial chemistry for the determination of effective molarity
Ciaccia, Maria,Tosi, Irene,Baldini, Laura,Cacciapaglia, Roberta,Mandolini, Luigi,Di Stefano, Stefano,Hunter, Christopher A.
, p. 144 - 151 (2015/02/19)
A new strategy for determining thermodynamic effective molarities (EM) for macrocylisation reactions using dynamic combinatorial chemistry under dilute conditions is presented. At low concentrations, below the critical value, Dynamic Libraries (DLs) of bifunctional building blocks contain only cyclic species, so it is not possible to quantify the equilibria between linear and cyclic species. However, addition of a monofunctional chain stopper can be used to promote the formation of linear oligomers allowing measurement of EM for all cyclic species present in the DL. The effectiveness of this approach was demonstrated for DLs generated from mixtures of 1,3-diimine calix[4]arenes, linear diaminoalkanes and monoaminoalkanes. For macrocycles deriving from one bifunctional calixarene and one diamine, there is an alternating pattern of EM values with the number of methylene units in the diamine: odd numbers give significantly higher EMs than even numbers. For odd numbers of methylene units, the alkyl chain can adopt an extended all anti conformation, whereas for even numbers of methylene units, gauche conformations are required for cyclisation, and the associated strain reduces EM. The value of EM for the five-carbon linker indicates that this macrocycle is a strainless ring. This journal is
PREPARATION OF DIAMINE VIA THE PREPARATION OF AMINONITRILE
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Paragraph 0128; 0129 - 0132, (2014/02/15)
A continuous method (P) for preparing diamine is described. The method includes reacting the corresponding alkene nitrile with the corresponding monoamine in order to form the corresponding aminonitrile. The monoamine can be introduced in molecular excess with respect to the alkene nitrile, wherein the unreacted monoamine is recirculated to the reaction; followed by reducing the aminonitrile produced by hydrogen in the presence of at least one alkali-metal hydroxide, water, and a hydrogenation catalyst; and purifying the diamine.
DMAPN Having a Low DGN Content and a Process for Preparing DMAPA from DMAPN Having a Low DGN Content
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Page/Page column 6-7, (2012/02/06)
The present invention relates to a process for preparing 3-dimethylaminopropylamine (DMAPA) by reacting 3-dimethylaminopropionitrile (DMAPN) with hydrogen in the presence of a catalyst, wherein the DMAPN used has a content of 2-(dimethylaminomethyl)glutaronitrile (DGN) of 300 ppm by weight or less, based on the DMAPN used. Furthermore, the present invention relates to mixtures of DMAPN and DGN, wherein the weight ratio of DMAPN to DGN is in the range from 1 000 000:5 to 1 000 000:250.
PROCESS FOR HYDROGENATING NITRILES
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Page/Page column 8, (2012/10/08)
The present invention relates to a process for hydrogenating nitriles by means of hydrogen in the presence of a catalyst in a reactor, where the catalyst is arranged in a fixed bed, wherein the cross-sectional loading in the reactor is in the range from 5 kg/(m2s) to 50 kg/(m2s). The present invention further relates to a process for preparing downstream products of isophoronediamine (IPDA) or N,N-dimethylaminopropylamine (DMAPA) from amines prepared according to the invention.
PROCESS FOR HYDROGENATING NITRILES
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Page/Page column 8, (2012/10/08)
The present invention relates to a process for hydrogenating organic nitriles by means of hydrogen in the presence of a catalyst in a reactor, where the shaped body catalyst is arranged in a fixed bed, wherein the shaped body in the shape of spheres or rods has in each case a diameter 3 mm or less, in the shape of tablets a height of 4 mm or less, and in the case of all other geometries in each case has an equivalent diameter L=1/a′ of 0.70 mm or less, where a′ is the external surface area per unit volume (mms2/mmp3), where: a ′ = A p V p , where Ap is the external surface area of the catalyst particle (mms2) and Vp is the volume of the catalyst particle (mmp3). The present invention further relates to a process for preparing downstream products of isophoronediamine (IPDA) or N,N-dimethylaminopropylamine (DMAPA) from amines prepared according to the invention.
HYDROGENATION CATALYSTS, THE PRODUCTION AND THE USE THEREOF
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Page/Page column 11, (2012/01/13)
The present invention relates to catalysts and processes for preparation thereof, said catalysts being obtainable by contacting a monolithic catalyst support with a suspension which comprises one or more insoluble or sparingly soluble compounds of the elements selected from the group of the elements cobalt, nickel and copper. The invention further relates to the use of the inventive catalyst in a process for hydrogenating organic substances, especially for hydrogenating nitriles, and to a process for hydrogenating organic compounds, which comprises using an inventive catalyst in the process.
METHOD FOR IMPROVING THE CATALYTIC ACTIVITY OF MONOLITHIC CATALYSTS
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Page/Page column 12, (2012/01/13)
The present invention relates to a process for improving the catalytic properties of a catalyst comprising one or more elements selected from the group consisting of cobalt, nickel and copper, said catalyst being present in the form of a structured monolith, by contacting the catalyst with one or more basic compounds selected from the group of the alkali metals, alkaline earth metals and rare earth metals. The invention further relates to a process for hydrogenating compounds which comprise at least one unsaturated carbon-carbon, carbon-nitrogen or carbon-oxygen bond in the presence of a catalyst comprising one or more elements selected from the group consisting of cobalt, nickel and copper, said catalyst being present in the form of a structured monolith, by contacting the catalyst with one or more basic compounds selected from the group of the alkali metals, alkaline earth metals and rare earth metals. The present invention also relates to the use of a basic compound selected from the group of the alkali metals, alkaline earth metals and rare earth metals for improving the catalytic properties of a catalyst comprising cobalt and/or copper and/or nickel, said catalyst being present in the form of a structured monolith.
