753-90-2Relevant articles and documents
METHOD FOR MANUFACTURE OF 1,1,1-TRIFLUORO-2-CHLOROETHANE (HCFC 133A) AND/OR TRFLUOROETHYLAMINE (TFEA)
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Page/Page column 28, (2020/06/05)
A method for manufacture of 1, 1, 1-trifluoro-2-chloroethane (HCFC-133a) and/or trifluoroethylamine (TFEA), wherein at least one reaction step takes place in a microreactor that is comprising or is made of SiC-microreactor, the processes can be efficiently combined in that HCFC-133a produced by using a microreactor, may preferably advantageously serve as starting material and/or intermediate material in the manufacture of TFEA. The HCFC-133a and/or the TFEA can be easily, by a method with only low energy consumption, purified and/or isolated, and preferably the process for purifying and/or isolating does not require a distillation. Advantageously, the separation from excess hydrogen fluoride (HF) and catalyst can easily take place in an energy-saving manner by phase separation.
Catalytic preparation method of trifluoroethylamine compound
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Paragraph 0042-0052, (2019/01/14)
The invention provides a preparation method of 2,2,2-trifluoroethylamine. Trifluoroformaldehyde or trifluoroacetaldehyde hydrate and ammonia water are taken as raw materials and subjected to reactionin the presence of a mesoporous molecular sieve supported catalyst and a suitable hydrogen donor, a product is subjected to secondary reduction, and trifluoroethylamine is prepared. The process does not need high temperature or high pressure, has mild reaction conditions, high conversion rate, few byproducts and low cost, is clean and environmentally friendly, conforms to the trend of green chemical industry nowadays and has higher industrial production value, and a catalyst is easy to recycle.
Catalytic reduction of amides to amines by electrophilic phosphonium cations via FLP hydrosilylation
Augurusa, Alessandra,Mehta, Meera,Perez, Manuel,Zhu, Jiangtao,Stephan, Douglas W.
supporting information, p. 12195 - 12198 (2016/10/21)
A catalytic methodology for the conversion of amides to amines is reported. Of the 25 examples described, 14 examples involve the reduction of N-trifluoroacetamides to the corresponding trifluoroethylamines. These reductions are achieved by catalytic hydrosilylation of the amide mediated by an electrophilic phosphonium cation (EPC) catalyst.
Kinetic study of the formation of N-chloro compounds using N-chlorosuccinimide
Pastoriza, Cristina,Antelo, Juan Manuel,Crugeiras, Juan,Pena-Gallego, Angeles
, p. 407 - 418 (2014/05/06)
Second-order rate constants were determined for the chlorination reaction of 2,2,2-trifluoethylamine and benzylamine with N-chlorosuccinimide at 25 °C and an ionic strength of 0.5 M. These reactions were found to be of first order in both reagents. According to the experimental results, a mechanism reaction was proposed in which a chlorine atom is transferred between both nitrogenous compounds. Kinetics studies demonstrate that the hydrolysis process of the chlorinating agent does not interfere in the chlorination process, under the experimental conditions used in the present work. Free-energy relationships were established using the results obtained in the present work and others available in the literature for chlorination reactions with N-chlorosuccinimide, being the pKa range included between 5.7 and 11.22. Copyright
N-methylimidazole promotes the reaction of homophthalic anhydride with imines
Liu, Jian,Wang, Zheng,Levin, Aaron,Emge, Thomas J.,Rablen, Paul R.,Floyd, David M.,Knapp, Spencer
supporting information, p. 7593 - 7599 (2014/09/16)
The addition of N-methylimidazole (NMI) to the reaction of homophthalic anhydride with imines such as pyridine-3-carboxaldehyde-N-trifluoroethylimine (9) reduces the amount of elimination byproduct and improves the yield of the formal cycloadduct, tetrahydroisoquinolonic carboxylate 10. Carboxanilides of such compounds are of interest as potential antimalarial agents. A mechanism that rationalizes the role of NMI is proposed, and a gram-scale procedure for the synthesis and resolution of 10 is also described.
Probing the nature of the Co(III) ion in corrins: Comparison of reactions of aquacyanocobyrinic acid heptamethyl ester and aquacyano-stable yellow cobyrinic acid hexamethyl ester with neutral N-donor ligands
Chemaly, Susan M.,Kendall, Louise,Nowakowska, Monika,Pon, Dale,Perry, Christopher B.,Marques, Helder M.
, p. 1077 - 1083 (2013/03/13)
Equilibrium constants (log K) for substitution of coordinated H 2O in aquacyanocobyrinic acid heptamethyl ester (aquacyanocobester, ACCbs) and aquacyano-stable yellow cobyrinic acid hexamethyl ester (aquacyano-stable yellow cobester, ACSYCbs), in which oxidation of the C5 carbon of the corrin interrupts the normal delocalized system of corrins, by neutral N-donor ligands (ammonia, ethanolamine, 2-methoxyethylamine, N-methylimidazole, and 4-methylpyridine) have been determined spectrophotometrically as a function of temperature. Log K values increase with the basicity of the ligand, but a strong compensation effect between ΔH and ΔS values causes a leveling effect. The aliphatic amines with a harder donor atom produce ΔH values that are more negative in their reactions with ACSYCbs than with ACCbs, while the softer, aromatic N donors produce more negative ΔH values with ACCbs than with ACSYCbs. Molecular modeling (DFT, M06L/SVP, and a quantum theory of atoms in molecules analysis of the electron density) shows that complexes of the aliphatic amines with SYCbs produce shorter and stronger Co-N bonds with less ionic character than the Co-N bonds of these ligands with the cobester. Conversely, the Co-N bond to the aromatic N donors is shorter, stronger, and somewhat less ionic in the complexes of the cobester than in those of the SYCbs. Therefore, the distinction between the harder Co(III) in ACSYCbs and softer Co(III) in ACCbs, reported previously for anionic ligands, is maintained for neutral N-donor ligands.
Acid-catalysed chlorine transfer from N-chloramines to iodide ion: Experimental evidence for a predicted change in mechanism
Calvo, Paula,Crugeiras, Juan,Rios, Ana
supporting information; experimental part, p. 4137 - 4142 (2010/10/19)
Rate constants for acid catalysis of the reactions of N-chlorodimethylamine (1), N-chloro-2,2,2-trifluoroethylamine (2) and N,N-dichlorotaurine (3) with iodide ion were determined in H2O at 25°C and I = 0.5 (NaClO 4). The failure to detect significant catalysis by general acids of chlorine transfer from 1 to the nucleophile, together with the observed inverse solvent deuterium isotope effect on the hydronium ion-catalysed reaction (k H/kD = 0.37), indicates that this process occurs by protonation of 1 in a fast equilibrium step, followed by rate determining chlorine transfer to iodide ion. The appearance of general acid catalysis for the reactions of 2 and 3 shows that increasing the leaving group ability leads to a change to a concerted mechanism, which is suggested to be enforced by the absence of a significant lifetime of the protonated chloramine intermediate in the presence of iodide ion.
Biomimetic reductive amination under the continuous-flow reaction conditions
Soloshonok, Vadim A.,Catt, Hector T.,Ono, Taizo
body text, p. 261 - 265 (2010/04/05)
This study present a full account of continuous-flow reaction conditions for biomimetic reductive amination of fluorinated carbonyl compounds to corresponding amines and amino acids of biomedical importance. We demonstrate that simple silica-adsorbed DBU can be used as efficient catalysts for on-column 1,3-proton shift reaction, a key transformation in the biomimetic reductive amination process. This new on-column process features operationally convenient conditions, higher chemical yields, enantioselectivity and purity of the corresponding products as compared with traditional in-flask reactions. Moreover the removal of base-catalyst, the most delicate problem of the in-flask reactions, is not an issue in the on-column process, as the silica-adsorbed DBU or polymer-bound guanidine remains on the column and can be reused. This feature renders the overall process substantially more economical and synthetically efficient, in particular, for large-scale synthesis of the corresponding fluorinated amines and amino acids target.
Facile preparation of polyfluoroalkylated aldimines from polyfluoroalkanoic acids
Takagi, Jun,Takihana, Ryozo,Kuwano, Akiko,Uneyama, Kenji
, p. 1624 - 1628 (2008/02/05)
Polyfluoroalkylated aldimines were prepared by reducing polyfluoroalkyl imidoyl chlorides, which are readily available from polyfluoroalkanoic acids, with LTBA (lithium tri-tert-butoxyaluminum hydride). Georg Thieme Verlag Stuttgart.
Mechanisms of acid decomposition of dithiocarbamates. 1. Alkyl dithiocarbamates
Humeres, Eduardo,Debacher, Nito A.,Marta de S. Sierra,Franco, Jose Dimas,Schutz, Aldo
, p. 1598 - 1603 (2007/10/03)
The acid decomposition of some substituted methyldithiocarbamates was studied in water at 25°C in the range of rio -5 and pH 5. The pH-rate profiles showed a bell-shaped curve from which were calculated the acid dissociation constants of the free and conjugate acid species and the specific acid catalysis rate constants k(H). The Bronsted plot of k(H) vs pK(N), the dissociation constant of the conjugate acid of the parent amine, suggests that the acid cleavage occurs through two mechanisms that depend on the pK(N). The plot presents a convex upward curve with a maximum at pK(N) 9.2, which is consistent with the cleavage of the dithiocarbamate anion through a zwitterion intermediate and two transition states. For pK(N) 9.2, the C-N bond breakdown is the slowest step, and according to the inverse SIE, the transition state changes rapidly with the increase of pK(N) to a late transition state. The plot shows a minimum at pK(N) ?10, indicating that a new mechanism emerges at higher values, and it is postulated that it represents a path of intramolecular S to N proton-transfer concerted with the C-N bond breakdown. The thiocarbonyl group acts as a powerful electron- withdrawing group, decreasing the basicity of the nitrogen of the parent amine by 14.1 pK units.
