100-23-2Relevant articles and documents
Safe and efficient reductive methylation of primary and secondary amines using N-methylpyrrolidine zinc borohydride
Alinezhad, Heshmatollah,Tajbakhsh, Mahmood,Salehian, Fatemeh,Fazli, Kazem
, p. 2415 - 2420 (2010)
An efficient, general procedure for reductive methylation of primary and secondary amines with 37% formaldehyde using N-methylpyrrolidine zinc borohydride (ZBHNMP) as a reducing agent gave the corresponding tertiary amines in excellent yields. The reaction was carried out in tetrahydrofuran under neutral conditions at 0-10°C. Copyright Taylor & Francis Group, LLC.
Photochemical Reaction of N,N-Dimethylanilines with N-Substituted Maleimides Utilizing Benzaldehyde as the Photoinitiator
Nikitas, Nikolaos F.,Theodoropoulou, Maria A.,Kokotos, Christoforos G.
, p. 1168 - 1173 (2021)
Photoorganocatalysis constitutes a powerful domain of photochemistry and organic synthesis. The scaffold of pyrrolo[3,4-c]quinolinoles exhibits interesting and potent inhibition against various enzymes, making them really promising pharmaceutical targets. Herein, we describe a photochemical methodology for the reaction of N,N-dimethylanilines with N-substituted maleimides, utilizing benzaldehyde as the photoinitiator. A variety of substituted N,N-dimethylanilines and N-substituted maleimides were converted into the corresponding adducts in moderate to high yields.
Deoxygenation of Tertiary Amine Oxides with Carbon Disulfide
Yoshimura, Toshiaki,Asada, Kaoru,Oae, Shigeru
, p. 3000 - 3003 (1982)
Reduction of various tertiary amine oxides with carbon disulfide was examined and kinetic experiments were carried out.Trialkylamine oxides and N,N-dialkylarylamine N-oxides were readily reduced by CS2 to give the corresponding tertiary amines in good yields, while heteroaromatic amine N-oxides such as picoline N-oxide were not affected.The oxygen atom in the N-oxide was found to be transferred to CO2 upon mass spectral analysis of the gas evolved.The kinetic experiments were carried out following the UV spectra of N,N-dimethylaniline N-oxide in CH3CN containing much excess of CS2 and the rate was found to be of 2nd order in the N-oxide and CS2.Activation parameters (ΔH=55.7 kJ mol-1, ΔS=-78.2 J K-1 mol-1 at 20 deg C) are characteristic of a normal bimolecular reaction.The logarithms of the rate constants for para-substituted N,N-dimethylaniline N-oxides are nicely correlated with Hammett ? values and a small negative ρ value (ρ=-0.2) was obtained.The rate of reaction was faster in polar aprotic solvents than in nonpolar or protic solvents.These observations seem to suggest that the reaction proceeds via an initial nucleophilic attack of the N-oxide oxygen at carbon disulfide followed by the rate-determining N-O bond fission to give the tertiary amine.
Demonstrating the Synergy of Synthetic, Mechanistic, and Computational Studies in A Regioselective Aniline Synthesis
Davies, Ian W.,Marcoux, Jean-Francois,Kuethe, Jeffery T.,Lankshear, Michael D.,Taylor, Jeremy D. O.,Tsou, Nancy,Dormer, Peter G.,Hughes, David L.,Houk,Guner, Vildan
, p. 1298 - 1308 (2004)
Tri- and tetrasubstituted anilines are formed in good to excellent yields by the addition of ketones to vinamidinium salts (up to 98%). The reaction proceeds via the formation of dienone intermediates, which react to form an enamine with the liberated amine. In the case of a nitro, or dimethylaminomethylene substituent, the enamines undergo a facile electrocyclic ring closure to form a cyclohexadiene, which goes on to form anilines with a high degree of selectivity (up to 50:1) with a minor competing pathway proceeding via the enol providing phenols. Competition experiments using isotopic substitution reveal that the rate determining step en route to dienone is enol/enolate addition to the vinamidinium salt, which is characterized by an inverse secondary isotope effect (kH/D 0.7-0.9). Computational studies have been used to provide a framework for understanding the reaction pathway. The original proposal for a [1,5]-H shift was ruled out on the basis of the calculations, which did not locate a thermally accessible transition state. The minimum energy conformation of the enamine is such that a facile electrocyclic ring closure is ensured, which is corroborated by the experimental studies. A framework for understanding the reaction pathway is presented.
Selective utilization of methoxy groups in lignin for: N -methylation reaction of anilines
Mei, Qingqing,Shen, Xiaojun,Liu, Huizhen,Liu, Hangyu,Xiang, Junfeng,Han, Buxing
, p. 1082 - 1088 (2019)
The utilization of lignin as a feedstock to produce valuable chemicals is of great importance. However, it is a great challenge to produce pure chemicals because of the complex structure of lignin. The selective utilization of specific groups on lignin molecules offers the possibility of preparing chemicals with high selectivity, but this strategy has not attracted attention. In this work, we propose a protocol to produce methyl-substituted amines by the selective reaction of the methoxy groups of lignin and aniline compounds. It was found that LiI in the ionic liquid 1-hexyl-3-methylimidazolium tetrafluoroborate could catalyze the reaction efficiently and the selectivity to the N-methylation product could be as high as 98%. Moreover, the lignin was not depolymerized in the reaction. As it was rich in hydroxyl groups, the residual material left over after the reaction was used as an efficient co-catalyst for the cycloaddition of epoxy propane with CO2, using KI as the catalyst.
Iron-catalyzed aryl-aryl cross coupling route for the synthesis of 1-(2-amino)-phenyl)dibenzo[b,d]furan-2-ol derivatives and their biological evaluation
Chiranjeevi, Barreddi,Koyyada, Ganesh,Prabusreenivasan,Kumar, Vanaja,Sujitha, Pombala,Kumar, C. Ganesh,Sridhar,Shaik, Saida,Chandrasekharam, Malapaka
, p. 16475 - 16485 (2013)
Naturally occurring dibenzofuran motifs represent promising lead structures for the development of novel antimycobacterial agents. Prompted by our recent development of cross dehydrogenative coupling using iron catalysis, we extended our strategy to synthesize 14 novel anilinodibenzofuranols and they were explored for anti-tubercular and cytotoxic activities. Consistent with our hypothesis, DBF-3, 14 and 16 exhibited promising activity against two strains (M. tuberculosis H37Rv and the clinical S, H, R, and E resistant isolate), while DBF-13, 18 exhibited selective inhibitory activity only against the clinical S, H, R and E resistant isolate. However, the compounds DBF-4 and DBF-8 showed promising and selective antitumor activity against the tested cancer cell lines. The Royal Society of Chemistry 2013.
A quantitative assessment of the production of OH and additional oxidants in the dark Fenton reaction: Fenton degradation of aromatic amines
Minero, Claudio,Lucchiari, Mirco,Maurino, Valter,Vione, Davide
, p. 26443 - 26450 (2013)
This paper reports the results of a kinetic study into the transformation of 2,4- and 3,4-dichloroaniline (2,4-DCA, 3,4-DCA) and of methyl yellow (MY) with the Fenton reagent in aqueous solution. All the substrates can be degraded in the presence of Fe(II) + H2O2, but the reaction between Fe(II) and H2O2 causes substrate degradation and Fe(II) oxidation within seconds under the adopted conditions. The HPLC, GC-MS and IC analyses only allow the monitoring of the reaction after all Fe(II) has been consumed, when degradation proceeds more slowly via Fe(III) reduction to Fe(II). Substrate degradation in the first part of the reaction was studied by stopped-flow spectrophotometry, using MY as substrate. The results are consistent with a reaction involving OH, where both Fe(II) and H 2O2 compete with MY for the hydroxyl radical. However, the experimental data indicate that OH is unlikely to be the only product of the reaction between Fe(II) and H2O2. Another species, possibly the ferryl ion (FeO2+), is formed as well but has a negligible role in MY degradation. The Fenton reaction would thus yield both OH (about 60% at pH 2) and ferryl (about 40%), and the 60:40 branching ratio between OH and the other species is compatible with additional data here reported concerning the degradation of 2,4-DCA and 3,4-DCA in the first ferrous step of the Fenton reaction. The reported findings will hopefully indicate a way out of a long-lasting controversy concerning the mechanism of the Fenton process, also suggesting an approach to quantitatively determine the formation yields of the reactive species as well as a strategy to identify the reactant that is actually involved in substrate transformation.
Traceless Directing-Group Strategy in the Ru-Catalyzed, Formal [3 + 3] Annulation of Anilines with Allyl Alcohols: A One-Pot, Domino Approach for the Synthesis of Quinolines
Kumar, Gangam Srikanth,Kumar, Pravin,Kapur, Manmohan
, p. 2494 - 2497 (2017)
A unique, ruthenium-catalyzed, [3 + 3] annulation of anilines with allyl alcohols in the synthesis of substituted quinolines is reported. The method employs a traceless directing group strategy in the proximal C-H bond activation and represents a one-pot Domino synthesis of quinolines from anilines.
Air-tolerant direct reductive N-methylation of amines using formic acid via simple inorganic base catalysis
Huang, Yan,Deng, Wei,Lin, Bo-Lin
, (2019)
The construction of N-methyl amine moieties is an important reaction that has found numerous applications. Development of new methylation agents that are more environmentally benign than classical agents, such as iodomethane and methyl sulfate, is still highly desirable. Herein, we report a convenient protocol for direct reductive N-methylation of amines using formic acid as the methylation agent via simple inorganic base catalysis. The present protocol operates under transition-metal-free and air-tolerant conditions. Both the catalyst, K2HPO4, and the reductant, polymethylhydrosiloxane (PMHS), are cheap and easily separable from the crude reaction product mixture. Mechanistic investigations suggest that the reaction occur through the formation of an acetal intermediate followed by the C–N bond formation.
1,4-Dioxane-Tuned Catalyst-Free Methylation of Amines by CO2 and NaBH4
Guo, Zhiqiang,Zhang, Bo,Wei, Xuehong,Xi, Chanjuan
, p. 2296 - 2299 (2018)
A catalyst-free reductive functionalization of CO2 with amines and NaBH4 was developed. The N-methylation of amines was carried out with CO2 as a C1 building block and 1,4-dioxane as the solvent. Notably, the six-electron reduction of CO2 to form the methyl group occurred simultaneously with formation of the C?N bond to give the N-methylated amine.
