- Synthesis of 2-(dimethylamino)ethanol by the hydrogenolysis of tris(2-hydroxyethyl)amine
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A new reaction for the selective hydrogenolysis of tris(2-hydroxyethyl)amine into 2-(dimethylamino)ethanol by molecular hydrogen over metallic palladium catalyst is disclosed.
- Kiyoura, Tadamitsu,Muraishi, Teruo
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- METHOD FOR PRODUCING CIS- AND TRANS-ENRICHED MDACH
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A process for preparing trans-enriched MDACH, including: distilling an MDACH starting mixture in the presence of an auxiliary, which is an organic compound having a molar mass of 62 to 500 g/mol, a boiling point at least 5° C. above the boiling point of cis,cis-2,6-diamino-1-methylcyclohexane, and 2 to 4 functional groups, each of which is independently an alcohol group or a primary, secondary or tertiary amino group. The MDACH starting mixture includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, based on the total amount of MDACH present in the MDACH starting mixture. The MDACH starting mixture includes both trans and cis isomers. Trans-enriched MDACH includes 0 to 100% by weight of 2,4-MDACH and 0 to 100% by weight of 2,6-MDACH, where the proportion of trans isomers in the mixture is higher than the proportion of trans isomers in the MDACH starting mixture.
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- RANEY nickel-catalyzed reductive N-methylation of amines with paraformaldehyde: Theoretical and experimental study
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RANEY Ni-catalyzed reductive N-methylation of amines with paraformaldehyde has been investigated. This reaction proceeds in high yield with water as a byproduct. RANEY Ni can be easily recovered and reused with a slight decrease of the yield. Using density functional theory (DFT), the mechanism of RANEY Ni-catalyzed reductive N-methylation is discussed in detail. The reaction pathway involves the addition of amine with formaldehyde, dehydration to form the imine and hydrogenation. In the transition state of hemiaminal dehydration, the C-O bond cleavage of the aromatic amine is more difficult than that of the aliphatic amine. For the aromatic amine, a higher energy barrier must be overcome, which results in a relatively low yield. After addition of amine with formaldehyde and dehydration, imine is obtained and preferred to adsorb on the bridge site of the Ni(111) surface. The preferential pathways of imine hydrogenation involve the pre-adsorbed hydrogen atom attacking the nitrogen atom of the imine. The energy barrier of hydrogenation is much lower than that of addition and dehydration. Thus, the hydrogenation of imine is a relatively rapid reaction step. In the reductive N-methylation of secondary amine, the possible dehydration pathway is different from the one of the primary amine. In the dehydration of the secondary amine, the intermediate hemiaminal is initially adsorbed on the bridge site of the Ni(111) surface, then undergoes C-O bond cleavage, and eventually the hydroxyl is located in the bridge site. With the final hydrogenation, the product is obtained by adsorption on the top site of the Ni(111) surface.
- Ge, Xin,Luo, Chenxi,Qian, Chao,Yu, Zhiping,Chen, Xinzhi
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p. 43195 - 43203
(2015/02/19)
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- Process for producing alkanolamines
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A process for producing an alkanolamine includes supplying a reactive distillation apparatus having an inner contacting surface which simultaneously facilitates a reaction process and a distillation process, feeding a first reactant including an amine represented by R′3-XNHX, wherein R′ is a hydrocarbon group, and X is 1, 2, or 3, feeding a second reactant including an akylene oxide represented by R″O, wherein R″ is a C2-C10-alkylene, feeding a catalyst in an amount from 0% to about 15% by weight of a mixture of the first reactant, the second reactant and the catalyst; recycling an overhead output from an overhead portion including an unreacted portion of the amine and the catalyst to achieve a substantially total reflux of the amine and the catalyst, and collecting a product output including an alkanolamine, the alkanolamine being a member selected from the group consisting of a monoalkanolamine, a dialkanolamine, and a trialkanolamine.
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- Process for producing 1,3-dialkyl-2-imidazolidinone compound
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There is provided a process for preparing a 1,3-dialkyl-2-imidazolidinone by using an alkylene oxide as a first component, using at least one of (A) carbon dioxide and a monoalkylamine; (B) a carbon dioxide compound of the monoalkylamine; and (C) an 1,3-dialkylurea, reacting the first and second components by heating at 50 ° C. or higher to give 1,3-dialkyl-2-imidazolidinone, characterized in that the total molar amount of a molar feed amount of the monoalkylamine included in the component (A), a molar feed amount of the monoalkylamine part of the carbon dioxide compound of monoalkylamine, component (B), and the double of a molar feed amount of the 1,3-dialkylurea, component (C), is at least three folds of a molar feed amount of the alkylene oxide. The preparation process of this invention uses an industrially readily available alkylene oxide as a starting material and can be suitably conducted with a higher yield in an industrial scale.
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- Additives and products including oligoesters
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The present invention relates to oligoesters and their use or the creation of additives. Oligoester containing additives and/or oligoesters themselves may be used for formulating pharmaceutical preparations, cosmetics or personal care products such as shampoos and conditioners. These oligoesters are particularly useful for the creation of multi-purpose additives that can impart conditioning, long substantivity and/or UV protection. Individual oligoesters and oligoester mixtures are described.
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- NMR Studies of the Conjugation of Mechlorethamine with Glutathione
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Many cancer cells are resistant to chemotherapeutic treatment with mechlorethamine and other alkylating agents.These drug-resistant cells often show an increase in the intracellular concentration of glutathione and an increase in the activity of glutathione-S-transferase when compared to the sensitive cells.Both of these components are thought to be involved with inactivation of the drug either through conjugation with glutathione or by hydrolysis.NMR spectroscopy was used to monitor the nonenzymatic conjugation of mechlorethamine with glutathione.Several intermediates along the pathway to the doubly glutathione substituted mustard, including both mustard-aziridinium adducts, can be observed.The assignment of the 1H NMR spectrum of these adducts are presented.At 30 deg C, pH 7.0, no hydrolyzed mustard was detectable.With the use of 13C-labeled mustard, the conjugation reaction can be shown to proceed through an aziridinium intermediate rather than by direct nucleophilic substitution.
- Gamcsik, Michael P.,Hamill, Terence G.,Colvin, Michael
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p. 1009 - 1014
(2007/10/02)
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- Chemistry of Nitrogen Mustard studied by Nuclear Magnetic Resonance Spectroscopy
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Reactions of the nitrogen mustard drug 2-chloro-N-(2-chloroethyl)-N-methylethanamine with nucleophiles in aqueous solution have been studied by 1H and 13C n.m.r. spectroscopy.Conditions have been devised for converting the mustard into the N-2-chloroethyl-N-methylaziridinium ion which has been characterized by 1H n.m.r. spectroscopy.To assist the studies of reactions of the mustard by 13C n.m.r. spectroscopy, it has been prepared labelled at both C-2 atoms by 13C.It is shown that reactions of the mustard with strong nucleophiles (e.g. thiosulphate) proceed to a product of disubstitution, without the aziridinium ion being detected spectroscopically, although its intermediacy is inferred by examining the distribution of 13C in product from 13C-labelled mustard.Less reactive nucleophiles (e.g. thiourea) yield a product of disubstitution via spectroscopically detected intermediates (aziridinium ion and monosubstituted intermediate).Relatively weak nucleophiles (e.g. guanosine) did not give detectable products of substitution; cis- and trans-NN'-2-chloroethyl-NN'-methylpiperazinium dichloride were formed via the aziridinium ion.The reaction of the mustard with excess of ammonia gives a 3 : 2 ratio of 2-amino-N-(2-aminoethyl)-N-methylethanamine and N-methylpiperazine.The distribution of 13C label in these products derived from 13C-labelled drug shows that the triamine is formed via aziridinium intermediates, whilst the piperazine arises via intramolecular cyclisation of the intermediate 2-amino-N-(2-chloroethyl)-N-methylethanamine.
- Golding, Bernard T.,Kebbell, Michael J.,Lockhart, Ian M.
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p. 705 - 714
(2007/10/02)
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