103-67-3Relevant articles and documents
Formylation of amines through catalyst- and solvent-free transamidation reaction
Lebleu, Thomas,Kotsuki, Hiyoshizo,Maddaluno, Jacques,Legros, Julien
, p. 362 - 364 (2014)
The transamidation between formamide and various amines proceeds under heating, without any catalyst nor solvent, providing thus green and neutral conditions for the formylation of primary and secondary amines. The resulting amide product can be directly transformed, in a one pot sequence, into monomethylamine.
Mechanism of α-Amino Acids decomposition in the gas phase. Experimental and theoretical study of the elimination kinetics of N-Benzyl Glycine Ethyl Ester
Tosta, Maria,Oliveros, Jhenny C.,Mora, Jose R.,Cordova, Tania,Chuchani, Gabriel
, p. 2483 - 2488 (2010)
The gas-phase elimination kinetics of N-benzylglycine ethyl ester was examined in a static system, seasoned with allyl bromide, and in the presence of the free chain radical suppressor toluene. The working temperature and pressure range were 386.4-426.7 °C and 16.7-40.0 torr, respectively. The reaction showed to be homogeneous, unimolecular, and obeys a first-order rate law. The elimination products are benzylglycine and ethylene. However, the intermediate benzylglycine is unstable under the reaction conditions decomposing into benzyl methylamine and CO2 gas. The variation of the rate coefficients with temperature is expressed by the following Arrhenius equation: log k1 (s-1) = (11.83 ± 0.52) - (190.3 ± 6.9) kJ mol -1 (2.303RT)-1. The theoretical calculation of the kinetic parameters and mechanism of elimination of this ester were performed at B3LYP/6-31G*, B3LYP/6-31+G**, MPW1PW91/6-31G*, and MPW1PW91/6-31+G** levels of theory. The calculation results suggest a molecular mechanism of a concerted nonsynchronous six-membered cyclic transition state process. The analysis of bond order and natural bond orbital charges implies that the bond polarization of C(=O)O-C, in the sense of C(=O)Oδ-...Cδ+, is rate determining. The experimental and theoretical parameters have been found to be in reasonable agreement.
New catalyst systems for iron-catalyzed hydrosilane reduction of carboxamides
Tsutsumi, Hironori,Sunada, Yusuke,Nagashima, Hideo
, p. 6581 - 6583 (2011)
A heptanuclear iron carbonyl cluster, [Fe3(CO) 11(μ-H)]2Fe(DMF)4 (4), is found to be a highly efficient catalyst for the reduction of various carboxamides by 1,2-bis(dimethylsilyl)benzene (BDSB), which makes possible reducing the amount of the catalyst, shortening the reaction time, and lowering the reaction temperatures.
Methylthio Activating Groups in the Synthesis of Isoquinolines
Euerby, Melvin R.,Waigh, Roger D.
, p. 127 - 128 (1984)
Methylthio activating groups have been found to improve the yields in six different isoquinoline syntheses: in four cases the improvement was from zero, in the unactivated system, to between 54 and 94percent.
Reactions of N-Halobenzylalkylamines with Sodium Methoxide in Methanol
Cho, Bong Rae,Yoon, Jong Chan,Bartsch, Richard A.
, p. 4943 - 4946 (1985)
Reactions of N-halobenzylmethylamines 1 and 2 (X = Cl and Br) with MeONa-MeOH have been investigated.Eliminations from 1 were quantitative, producing only benzylidenemethylamines.Reaction of 2 with MeONa-MeOH produced benzylidenemethylamines and benzylmethylamines.The yield of benzylidenemethylamine increased with electron-withdrawing aryl substituents and increased base concentration and became quantitative when pentane was used as a solvent.The results are interpreted as competing bimolecular elimination and nucleophilic substitution by methoxide on bromine.Product studies for reaction of N-halobenzyl-tert-butylamines with MeONa-MeOH and EtSNa-MeOH establish that the substitution reaction is a general reaction pathway available for the N-haloamines.Transition states for eliminations from 1 and 2 are characterized by Hammett ρ and primary deuterium isotope effect values.
Organolanthanide-catalyzed imine hydrogenation. Scope, selectivity, mechanistic observations, and unusual byproducts
Obora, Yasushi,Ohta, Tetsuo,Stern, Charlotte L.,Marks, Tobin J.
, p. 3745 - 3755 (1997)
In this paper we report the Cp'2LnMe2SiCp''2Ln-catalyzed (Cp' = η5-Me5C5; Cp'' = η5-Me4C5) hydrogenation of acyclic imines to yield the corresponding amines. At 190 psi of H2, the observed turnover frequencies (h-1) (100:1 substrate:catalyst ratio, Cp'2Ln, temperature (°C)) are (1) (N-benzylidene(methyl)amine, Ln = La, 50) 0.03; (Ln = Sm, 90) 1.0; (Ln = Sm + PhSiH3, 90) 2.2; (Ln = Lu, 90) 0.60; (2) (N-benzylideneaniline, Ln = Sm, 90) 0.10; (3) (N-benzylidene(trimethylsilyl)amine, Ln = Sm, 90) 0.40; (4) (N-(α-methylbenzylidene)(methyl)amine, Ln = Sm, 90) 0.20; (5) (N-(α-methylbenzylidene)(benzyl)amine, Ln = Sm, 90) 0.70. The stoichiometric reaction of N-benzylidene(methyl)amine with Cp'2SmCH(SiMe3)2 or (Cp'2SmH)2 yields an orthometalated Cp'2Sm-substrate complex which undergoes either hydrogenolysis/hydrogenation or competing C=N insertion of a second substrate molecule to yield a Cp'2Sm-imine-amido complex with a seven-membered chelate ring. The stoichiometric reaction of 2-methyl-1-pyrroline with Cp'2SmCH(SiMe3)2 or (Cp'2SmH)2 yields a Cp'2Sm-imine-amido complex in which two substrate molecules have been coupled to form a six-membered chelate ring (characterized by X-ray diffraction). The stoichiometric reaction of N-benzylidene(trimethylsilyl)amine with (Cp'2SmH)2 yields a desilylated Cp'2Sm-imine-amido complex with a four-membered Sm(NSiMe3)(CPh)N=CHPh chelate ring (characterized by X-ray diffraction). Additional heating of this product under H2 yields S6-symmetric (Cp'2SmCN)6, which contains an unusual chairlike 18-membered (SmCN)6 ring (characterized by X-ray diffraction).
Reactions of N-Chlorobenzylmethylamines with Secondary Amines in Acetonitrile. Effect of Base Strength upon the Imine-Forming Transition State
Cho, Bong Rae,Namgoong, Sung Keon,Bartsch, Richard A.
, p. 1320 - 1324 (1986)
Reactions of N-chlorobenzylmethylamines 1 with R2NH in MeCN have been investigated kinetically.Eliminations from 1 were quantitative and regiospecific, producing only benzylidenemethylamines.For the elimination reaction of 1 with Bu2NH, kH/kD = 8.8, ρ = 0.96, ΔH(excit.) = 7.6 kcal/mol, and ΔS(excit.) = -45.1 eu were determined.The transition state structure is assessed as being highly symmetrical with similar extents of Cβ-H and Nα-Cl bond cleavage, little carbanionic character, and significant ? bond formation.The kH/kD and ρ values first increase and then decrease with enhancing amine base strength.Comparison of these results with those for related olefin-forming eliminations provides insight into the transition state differences between imine- and olefin-forming eliminations.
Reduction of amides with NaBH4 in diglyme at 162°C
Zhu, Hua-Jie,Lu, Kai-Tao,Sun, Guang-Ri,He, Jin-Bao,Li, Hai-Qing,Pittman Jr., Charles U.
, p. 409 - 413 (2003)
High temperature (162°C) reductions of aromatic amides were studied to extend the useful range of functional group transformations by NaBH4. Primary aromatic amides were reduced to the amines with NaBH4-diglyme at 162°C. Reduction proceeds via fast initial loss of hydrogen, followed by formation of the corresponding nitrile, which is then more slowly reduced to the amine. N-Methylbenzamide is not reduced under these conditions, but it is reduced to benzylmethylamine when LiCl is added to NaBH4-diglyme at 162°C. LiCl addition raised the rate of primary aromatic amide and aromatic nitrile conversions to both the nitrile, first, and the amine. An intermediate was isolated from the reaction of N-benzylformamide with NaBH4-LiCl in diglyme at 162°C. It was examined by 1H NMR, atomic absorption, IR and thermal decomposition. Possible structures are proposed. A mechanism for the reduction of primary aromatic amides is proposed based on the initial evolution of one mole equivalent of hydrogen and formation of the nitrile prior to further reduction to amine.
A mild method for cleavage of N-Tos protected amines using mischmetal and TiCl4
Vellem?e, Eerold,Lebedev, Oleg,M?eorg, Uno
, p. 1373 - 1375 (2008)
The para-toluenesulfonyl (Tos) protecting group is removed efficiently and quickly under neutral conditions from the corresponding protected primary and secondary amines using mischmetal in moderate to excellent yields.
Chelating bis-carbene rhodium(III) complexes in transfer hydrogenation of ketones and imines
Albrecht, Martin,Crabtree, Robert H.,Mata, Jose,Peris, Eduardo
, p. 32 - 33 (2002)
Chelating rhodium(III) carbene complexes are accessible via a simple synthesis and are catalytically active for hydrogen transfer from alcohols to ketones and imines.
