106-58-1Relevant articles and documents
Intermolecular cyclization of diethanolamine and methylamine to N,N′-dimethylpiperazine over zeolites under high pressure
Narender,Srinivasu,Kulkarni,Raghavan
, p. 430 - 433 (2001)
Synthesis of N,N′-dimethylpiperazine via intermolecular cyclization of diethanolamine and methylamine has been investigated under high pressure conditions using zeolites and montmorillonite K10 for the first time. The HZSM-5(30) is particularly effective
Continuous N-alkylation reactions of amino alcohols using γ-Al2O3 and supercritical CO2: Unexpected formation of cyclic ureas and urethanes by reaction with CO2
Streng, Emilia S.,Lee, Darren S.,George, Michael W.,Poliakoff, Martyn
, p. 329 - 337 (2017)
The use of γ-Al2O3 as a heterogeneous catalyst in scCO2 has been successfully applied to the amination of alcohols for the synthesis of N-alkylated heterocycles. The optimal reaction conditions (temperature and substrate flow rate) were determined using an automated self-optimising reactor, resulting in moderate to high yields of the target products. Carrying out the reaction in scCO2 was shown to be beneficial, as higher yields were obtained in the presence of CO2 than in its absence. A surprising discovery is that, in addition to cyclic amines, cyclic ureas and urethanes could be synthesised by incorporation of CO2 from the supercritical solvent into the product.
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Mann,Senior
, p. 4476,4480 (1954)
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N-methylation of nitrogen-containing heterocycles with dimethyl carbonate
Ouk, Samedy,Thiebaud, Sophie,Borredon, Elisabeth,Chabaud, Bernard
, p. 3021 - 3026 (2005)
Reactivity of dimethyl carbonate, the environmentally friendly reagent, as methylating agent for nitrogen-containing heterocyclic compounds has been studied. Reactions of imidazole, pyrazole, pyrrole, morpholine, and piperazine with dimethyl carbonate to afford N-methylated products were reported. The reactions were carried out with neither catalyst nor solvent at a temperature range of 110-170°C under atmospheric pressure. Copyright Taylor & Francis, Inc.
Modified ZSM-5 Catalysts for the Synthesis of Five- and Six-Membered Heterocyclics
Subba Rao, Yarlagadda V.,Kulkarni, Shivanand J.,Subrahmanyam, Machiraju,Rama Rao, A. V.
, p. 3998 - 4000 (1994)
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An enthalpic scale of hydrogen-bond basicity. 3. Ammonia, primary, secondary, and tertiary amines
Graton, Jerome,Berthelot, Michel,Besseau, Francois,Laurence, Christian
, p. 7892 - 7901 (2005)
A reliable enthalpic scale of hydrogen-bond acceptor strength (basicity) is built for aliphatic amines by means of a new infrared method, from the temperature variation of hydrogen-bond equilibrium constants. Enthalpies of hydrogen bonding to a reference hydrogen-bond acceptor, 4-fluorophenol, have been determined in CCl4 and/or C2C14 for ammonia and 68 primary, secondary, and tertiary amines. The scale spans from -23.8 kJ mol -1 for i-Pr2NCH(Et)2 to -39.4 kJ mol -1 for Et3N. This large variation is mainly explained by the basicity-enhancing electronic effects of alkyl groups, which can be overcompensated by dramatic basicity-decreasing steric effects. Relationships between ΔH° and the change in electronic energy or the infrared shift of the OH stretching upon hydrogen bonding are studied and found useful in the prediction of the hydrogen bond enthalpies of amines with several hydrogen-bond acceptor sites. A careful statistical analysis of the enthalpy-entropy relationship shows an isoentropic tendency. The entropies of 65% of hydrogen-bonding reactions between aliphatic amines and 4-fluorophenol have a mean value of -55.1 ± 4.2 J K-1 mol-1. Amines excluded from the isoentropic set are mainly severely hindered ones. The hydrogen-bond enthalpic scale can be useful in measuring the electrostatic character of Lewis bases.
A METHOD FOR PREPARING ALKYLATED AMINES
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Page/Page column 31; 32, (2021/09/11)
The present invention pertains to a method for preparing an alkylated amine by reacting a primary or secondary amine with an alcohol in the presence of hydrogen, a metal catalyst supported by photosensitive titanium oxide, and UV irradiation. Advantageously, the reaction can be carried out under mild reaction conditions.
N-Methylation of Amines with Methanol in Aqueous Solution Catalyzed by a Water-Soluble Metal-Ligand Bifunctional Dinuclear Iridium Catalyst
Han, Xingyou,Li, Feng,Liu, Peng,Meng, Chong,Tung, Nguyen Thanh
, p. 5815 - 5824 (2020/05/26)
The N-methylation of amines with methanol in aqueous solution was proposed and accomplished by using a water-soluble metal-ligand bifunctional dinuclear iridium catalyst. In the presence of [(Cp*IrCl)2(thbpym)][Cl]2 (1 mol %), a range of desirable products were obtained in high yields under environmentally benign conditions. Notably, this research exhibited the potential of transition metal-catalyzed activation of methanol as a C1 source for the construction of the C-N bond in aqueous solution.