108-18-9Relevant articles and documents
Kinetics and mechanism of chlorine exchange between chloramine-T and secondary amines
Dannan,Crooks,Dittert,Hussain
, p. 652 - 656 (1992)
The kinetics and mechanisms of chlorine transfer from chloramine-T (CAT) to several amines are second order and independent of p-toluenesulfonamide concentration; thus, the reaction does not involve disproportionation of CAT to dichloramine-T. From the profile of pH versus rate, the following mechanisms were proposed: (1) reaction of the ionized species of CAT with the ionized amine (ionic mechanism) and (2) reaction of the un-ionized species of CAT with the un-ionized amine (nonionic mechanism). The second-order, pH- independent rate constants calculated for the ionic and nonionic mechanisms were 1.6 and 5 x 106 M-1 s-1, respectively. Although these two mechanisms are kinetically indistinguishable, the rate constant for the nonionic mechanism is of the same order of magnitude as those calculated for similar chlorination reactions involving nonionizable chloramines, such as N- chlorosuccinimide, N-chloroquinuclidine, and N-chloro-N- methylbenzenesulfonamide. The proposed mechanism for the chlorine exchange involves a molecule of water in a cyclic, six-membered transition state.
Transient Alkylaminium Radicals in n-Hexane. Condensed-Phase Ion-Molecule Reactions
Werst, D. W.,Trifunac, A. D.
, p. 1268 - 1274 (1991)
Time-resolved fluorescence detected magnetic resonance (FDMR) is used to observe alkylaminium radicals formed in n-hexane solutions by electron pulse radiolysis.The ease of observation of aminium radical FDMR signals increases with increasing alkyl substitution of the amine solutes.The results are discussed in terms of the ion-molecule reactions, such as proton transfer, which compete with electron-transfer processes, i. e., the electron transfer from solute molecules to n-hexane radical cations and geminate recombination.
Effect of an Alumina Phase on the Reductive Amination of 2-Propanol to Monoisopropylamine over Ni/Al2O3
Cho, Jun Hee,An, Sang Hee,Chang, Tae-Sun,Shin, Chae-Ho
, p. 811 - 819 (2016)
Various single-phase aluminum oxides were prepared through the thermal decomposition of bayerite, boehmite, and gibbsite. Ni/γ-Al2O3 and Ni/δ-Al2O3 catalysts exhibited higher monoisopropylamine (MIPA) selectivity than the η-, θ-, and κ-Al2O3 supported Ni catalysts for the reductive amination of 2-propanol (IPA) in the presence of hydrogen and ammonia. FT-IR spectra after pyridine adsorption showed that a high number of Lewis acid sites could be correlated with enhancement in MIPA selectivity. Ni/η-Al2O3 and Ni/γ-Al2O3 catalysts exhibited the highest catalytic activity arising from differences in the metallic surface area. Both catalyst activity and selectivity with regards to reductive amination were strongly affected by the nature of the support.
Oxidative Detoxification of Sulfur-Containing Chemical Warfare Agents by Electrophilic Iodine
Smolkin, Boris,Levi, Noam,Karton-Lifshin, Naama,Yehezkel, Lea,Zafrani, Yossi,Columbus, Ishay
, p. 13949 - 13955 (2018)
Mild oxidation of sulfur-containing chemical warfare agents was performed in organic medium by electrophilic iodine reagents. Kinetic experiments on sulfur mustard (HD) showed rapid (t1/2 1/2 ~ 90 min). Higher donor number solvents, such as THF, DMF, or DMSO, showed slower rates with both iodine and NIS. The oxidation of the nerve agent O-ethyl-S-2-(N,N-diisopropylaminoethyl)methylphosphonothioate (VX) selectively to the nontoxic ethyl methylphosphonic acid product exhibited fast rates (t1/2 = 6 min) using NIS in DMSO solution. In all other solvents tested with VX, rates were slower (t1/2 ~ 30-70 min). Oxidation experiments under the same conditions with chloroethyl ethyl sulfide (HD simulant) and O,S-diethyl methylphosphonothioate (VX simulant) led to much faster reaction rates. These transformations are believed to proceed through electrophilic iodine attack on the sulfur moiety and display solvent dependency based on the agents' structural and chemical properties.
Reductive amination of 2-propanol to monoisopropylamine over Co/γ-Al2O3 catalysts
Cho, Jun Hee,Park, Jung Hyun,Chang, Tae-Sun,Seo, Gon,Shin, Chae-Ho
, p. 313 - 319 (2012)
Co/γ-Al2O3 catalysts with 4-27 wt% cobalt loadings were prepared by incipient-wetness impregnation and used to catalyze the synthesis of monoisopropylamine by the reductive amination of 2-propanol in the presence of hydrogen and ammonia. The catalysts were characterized by X-ray diffraction, H2-temperature programmed reduction, N 2-sorption, and H2-chemisorption. 23 wt% Co loading resulted in the highest catalytic activity and a long-term stability of up to 100 h on stream. 2-Propanol conversion was related to the exposed metal surface area and the number of exposed cobalt atoms. In the absence of hydrogen, the catalyst was progressively deactivated; its initial activity and selectivity were completely recovered upon re-exposure to hydrogen. The deactivation was due to the formation of metal nitride caused by the strong adsorption of ammonia on the surface of the metal phase. Excess hydrogen hindered the phase transition to metal nitride, preventing deactivation.
Zirconocene-Initiated Intramolecular Hydride Transfer in N -Isoalkyl-Substituted Propargylamines
Ramazanov, Ilfir R.,Kadikova, Rita N.,Saitova, Zukhra R.,Dzhemilev, Usein M.
, p. 1191 - 1194 (2018)
The unusual transformation of N -isoalkyl-substituted propargylamines into alkenylamines under the action of Cp 2 ZrCl 2 and organoaluminum compounds (Me 3 Al, EtAlCl 2) has been observed. The proposed mechanism, involving the N -isoalkyl-substituted propargylamine undergoing zirconocene-initiated intramolecular hydride transfer was supported by B3LYP/6-31G(d)/LanL2DZ calculations.
Synthesis of Trialkylamines with Extreme Steric Hindrance and Their Decay by a Hofmann-like Elimination Reaction
Banert, Klaus,Hagedorn, Manfred,Heck, Manuel,Hertel, Raphael,Ihle, Andreas,Müller, Ioana,Pester, Tom,Shoker, Tharallah,Rablen, Paul R.
, p. 13630 - 13643 (2020/11/13)
A number of amines with three bulky alkyl groups at the nitrogen, which surpass the steric crowding of triisopropylamine considerably, were prepared by using different synthetic methods. It turned out that treatment of N-chlorodialkylamines with organometallic compounds, for example, Grignard reagents, in the presence of a major excess of tetramethylenediamine offered the most effective access to the target compounds. The limits of this method were also tested. The trialkylamines underwent a dealkylation reaction, depending on the degree of steric stress, even at ambient temperature. Because olefins were formed in this transformation, it showed some similarity with the Hofmann elimination. However, the thermal decay of sterically overcrowded tertiary amines was not promoted by bases. Instead, this reaction was strongly accelerated by protic conditions and even by trace amounts of water. Reaction mechanisms, which were analyzed with the help of quantum chemical calculations, are suggested to explain the experimental results.
Electroactivated alkylation of amines with alcohols: Via both direct and indirect borrowing hydrogen mechanisms
Appiagyei, Benjamin,Bhatia, Souful,Keeney, Gabriela L.,Dolmetsch, Troy,Jackson, James E.
supporting information, p. 860 - 869 (2020/02/21)
A green, efficient N-alkylation of amines with simple alcohols has been achieved in aqueous solution via an electrochemical version of the so-called "borrowing hydrogen methodology". Catalyzed by Ru on activated carbon cloth (Ru/ACC), the reaction works well with methanol, and with primary and secondary alcohols. Alkylation can be accomplished by either of two different electrocatalytic processes: (1) in an undivided cell, alcohol (present in excess) is oxidized at the Ru/ACC anode; the aldehyde or ketone product condenses with the amine; and the resulting imine is reduced at an ACC cathode, combining with protons released by the oxidation. This process consumes stoichiometric quantities of current. (2) In a membrane-divided cell, the current-activated Ru/ACC cathode effects direct C-H activation of the alcohol; the resulting carbonyl species, either free or still surface-adsorbed, condenses with amine to form imine and is reduced as in (1). These alcohol activation processes can alkylate primary and secondary aliphatic amines, as well as ammonia itself at 25-70 °C and ambient pressure.