- Ru-Catalyzed Selective Catalytic Methylation and Methylenation Reaction Employing Methanol as the C1 Source
-
Methanol can be employed as a green and sustainable methylating agent to form C-C and C-N bonds via borrowing hydrogen (BH) methodology. Herein we explored the activity of the acridine-derived SNS-Ru pincer for the activation of methanol to apply it as a C1 building block in different reactions. Our catalytic system shows great success toward the β-C(sp3)-methylation reaction of 2-phenylethanols to provide good to excellent yields of the methylated products. We investigated the mechanistic details, kinetic progress, and temperature-dependent product distribution, which revealed the slow and steady generation of in situ formed aldehyde, is the key factor to get the higher yield of the β-methylated product. To establish the environmental benefit of this reaction, green chemistry metrics are calculated. Furthermore, dimerization of 2-naphthol via methylene linkage and formation of N-methylation of amine are also described in this study, which offers a wide range of substrate scope with a good to excellent yield.
- Biswas, Nandita,Srimani, Dipankar
-
p. 10544 - 10554
(2021/07/31)
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- PRODUCTION OF AMINES VIA A HYDROAMINOMETHYLATION REACTION USING IMINIUM REACTANTS
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Provided is a process for producing an amine via a hydroaminomethylation reaction of a non- aromatic C-C double bond, said process comprising a step of reacting a compound comprising a non-aromatic C-C double bond with an iminium ion in a solvent comprising an alcohol, wherein the iminium ion is represented by the following formula (I): wherein R1 and R2 are independently hydrogen or selected from the group consisting of an aliphatic hydrocarbon group which may be substituted, an aromatic hydrocarbon group which may be substituted, an aliphatic heterocyclic group which may be substituted, an aromatic heterocyclic group which may be substituted and of combinations thereof, such as an aralkyl group which may be substituted; and R1 and R2 may be bonded to each other to form a ring together with the nitrogen atom to which they are bound; and wherein R1 and R2 are not both hydrogen and at least one of R1 and R2 carries a hydrogen atom at a carbon atom in ex? position to the nitrogen atom of the iminium ion.
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Page/Page column 29-30
(2020/05/14)
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- PRODUCTION OF AMINES VIA A HYDROAMINOALKYLATION REACTION
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Provided is a process for producing an amine via a hydroaminoalkylation reaction of a non-aromatic C-C double bond or C-C triple bond, said process comprising a step of reacting a compound comprising a non-aromatic C-C double bond or C-C triple bond with a reactive component which is obtainable by combining an aminal or a hemiaminal ether with an acidic medium comprising trifluoroacetic acid, wherein the aminal contains two amino groups independently selected from a secondary and a tertiary amino group that are linked by a methylene group wherein one hydrogen atom may be replaced by a further substituent, and at least one of the amino groups carries a hydrogen atom at a carbon atom bound in α-position to its nitrogen atom, and the hemiaminal ether contains a secondary or a tertiary amino group which carries a hydrogen atom at a carbon atom bound in α-position to its nitrogen atom, and the secondary or tertiary amino group is linked to an alkoxy group by a methylene group wherein one hydrogen atom may be replaced by a further substituent.
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Page/Page column 64-65; 69; 85-86
(2019/12/04)
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- A BEt3-Base catalyst for amide reduction with silane
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Reported herein is the development of a simple but practical catalytic system for the selective reduction of amides with hydrosilane or hydrosiloxane. Low-cost and readily available triethylborane (1.0 M in THF), in combination with a catalytic amount of an alkali metal base, was found to catalyze the reduction of all three amide classes (tertiary, secondary, and primary amides) to form amines under mild conditions. In addition, the selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved by using a proper combination of BEt3 and base. The scope of these BEt3-base-catalyzed amide hydrosilylation reactions has been explored in depth. Preliminary results of mechanistic studies suggest a modified Piers' silane Si-H···B activation mode wherein the hydride abstraction by BEt3 is promoted by the coordination of an alkoxide or hydroxide anion to the Si center.
- Yao, Wubing,Fang, Huaquan,He, Qiaoxing,Peng, Dongjie,Liu, Guixia,Huang, Zheng
-
-
- A BEt3-Base Catalyst for Amide Reduction with Silane
-
Reported herein is the development of a simple but practical catalytic system for the selective reduction of amides with hydrosilane or hydrosiloxane. Low-cost and readily available triethylborane (1.0 M in THF), in combination with a catalytic amount of an alkali metal base, was found to catalyze the reduction of all three amide classes (tertiary, secondary, and primary amides) to form amines under mild conditions. In addition, the selective transformation of secondary amides to aldimines and primary amides to nitriles can also be achieved by using a proper combination of BEt3 and base. The scope of these BEt3-base-catalyzed amide hydrosilylation reactions has been explored in depth. Preliminary results of mechanistic studies suggest a modified Piers' silane Si-H···B activation mode wherein the hydride abstraction by BEt3 is promoted by the coordination of an alkoxide or hydroxide anion to the Si center.
- Yao, Wubing,Fang, Huaquan,He, Qiaoxing,Peng, Dongjie,Liu, Guixia,Huang, Zheng
-
p. 6084 - 6093
(2019/05/24)
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- A General Acid-Mediated Hydroaminomethylation of Unactivated Alkenes and Alkynes
-
In comparison to the extensively studied metal-catalyzed hydroamination reaction, hydroaminomethylation has received significantly less attention despite its considerable potential to streamline amine synthesis. State-of-the-art protocols for hydroaminomethylation of alkenes rely largely on transition-metal catalysis, enabling this transformation only under highly designed and controlled conditions. Here we report a broadly applicable, acid-mediated approach to the hydroaminomethylation of unactivated alkenes and alkynes. This methodology employs cheap, readily available, and bench-stable reactants and affords the desired amines with excellent functional group tolerance and impeccable regioselectivity. The broad scope of this transformation, as well as mechanistic investigations and in situ domino functionalization reactions are reported.
- Kaiser, Daniel,Tona, Veronica,Gon?alves, Carlos R.,Shaaban, Saad,Oppedisano, Alberto,Maulide, Nuno
-
supporting information
p. 14639 - 14643
(2019/09/17)
-
- N-Methylation of amines and nitroarenes with methanol using heterogeneous platinum catalysts
-
We report herein the selective N-methylation of amines and nitroarenes with methanol under basic conditions using carbon-supported Pt nanoparticles (Pt/C) as a heterogeneous catalyst. This method is widely applicable to four types of N-methylation reactions: (1) N,N-dimethylation of aliphatic amines under N2, (2) N-monomethylation of aliphatic amines under 40 bar H2, (3) N-monomethylation of aromatic amines under N2, and (4) tandem synthesis of N-methyl anilines from nitroarenes and methanol under 2 bar H2. All these reactions under the same catalytic system showed high yields of the corresponding methylamines for a wide range of substrates, high turnover number (TON), and good catalyst reusability. Mechanistic studies suggested that the reaction proceeded via a borrowing hydrogen methodology. Kinetic results combined with density functional theory (DFT) calculations revealed that the high performance of Pt/C was ascribed to the moderate metal–hydrogen bond strength of Pt.
- Jamil, Md.A.R.,Touchy, Abeda S.,Rashed, Md. Nurnobi,Ting, Kah Wei,Siddiki, S.M.A. Hakim,Toyao, Takashi,Maeno, Zen,Shimizu, Ken-ichi
-
-
- ANIONIC-CATIONIC-NONIONIC SURFACTANT,PRODUCTION AND USE THEREOF
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This invention relates to an anionic-cationic-nonionic surfactant as substantially represented by the formula (I), production and use thereof in tertiary oil recovery. The anionic-cationic-nonionic surfactant of this invention exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present anionic-cationic-nonionic surfactant, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced. In the formula (I), each group is as defined in the specification.
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-
Paragraph 0260
(2017/11/16)
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- PROCESS FOR PRODUCING N-METHYL OR N,N-DIMETYL AMINES
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A process for producing N-methyl or N,N-dimethyl amines, which comprises using amine compound, nitro-containing compound or nitrile compound as a starting material, carbon dioxide as a methylating agent and hydrogen gas as a reducing agent, and allowing them to react in a sealed reactor for 6 to 48 h in a reaction medium at a reaction temperature of 80 to 180 ° C. in the presence of a composite catalyst, so as to provide N-methyl or N,N-dimethyl amines. The process of the present invention is simple and under relative mild reaction conditions. By means of the process of the invention, the target products can be prepared at low cost with a high yield. The catalysts used have a high catalytic activity and can be separated from the reaction system simply and reused. Furthermore, the whole process of the present invention is environmental-friendly and facilitates the cycling use of carbon dioxide.
- -
-
Paragraph 0059
(2015/02/18)
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- Methylation of amines, nitrobenzenes and aromatic nitriles with carbon dioxide and molecular hydrogen
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CO2/H2 was successfully employed in alkylation reactions by performing CO2 reduction and amine N-methylation in one-pot. In the presence of a simple CuAlOx catalyst, N-methyl or N,N-dimethyl amines with different structures can be selectively synthesized with up to 96% yields by applying amine, nitrobenzene and nitrile as starting materials.
- Cui, Xinjiang,Dai, Xingchao,Zhang, Yan,Deng, Youquan,Shi, Feng
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p. 649 - 655
(2014/01/17)
-
- Selective monomethylation of primary amines with simple electrophiles
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Direct monomethylation of primary amines with methyl triflate was achieved with high selectivity (up to 96%). The key point of this single methyl transfer stems from the use of HFIP as the solvent that interferes with amines and avoids overmethylation.
- Lebleu, Thomas,Ma, Xiaolu,Maddaluno, Jacques,Legros, Julien
-
supporting information
p. 1836 - 1838
(2014/02/14)
-
- Hg cathode-free electrochemical detosylation of N,N-disubstituted p-toluenesulfonamides: mild, efficient, and selective removal of N-tosyl group
-
Hg cathode-free electrochemical detosylation of N,N-disubstituted p-toluenesulfonamides was successfully carried out by a constant current electrolysis using an undivided cell equipped with a platinum cathode and a magnesium anode in the presence of an arene mediator. The deprotection proceeded efficiently and selectively under neutral and mild conditions with a stoichiometric amount of electricity without the use of an Hg cathode to obtain the corresponding secondary amines in good to excellent yields.
- Senboku, Hisanori,Nakahara, Kazuo,Fukuhara, Tsuyoshi,Hara, Shoji
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supporting information; experimental part
p. 435 - 438
(2010/03/04)
-
- Synthesis of nonsymmetrical dialkylamines on the basis of diphenylphosphinic amides
-
A facile method for the synthesis of nonsymmetrical dialkylamines (C nH2n+1)2NH (n = 1-12) using the Ph 2P(O) protecting group was developed. The method includes successive transformation of monoalkylamines to primary diphenylphosphinic N-alkylamides Ph2P(O)NHR' (R' = CnH2n+1, n = 1-12) by the Todd-Atherton reaction, phase transfer N-alkylation of these compounds, and hydrolysis of the secondary amides Ph2P(O)NR'R″ thus formed. When the (EtO)2P(O) and Bu2P(O) protecting groups are used, N-alkylation of primary amides is accompanied by the formation of Et-O and P-N bond cleavage products, respectively. A study of the stability of the N-alkylamides R2P(O)NHR' (R = Ph, p-MeC6H4, p-CIC6H4, Bu) under strong alkaline conditions used in the phase transfer N-alkylation showed that an increase in the electron-donating ability of substituents at both the nitrogen atom and the phosphorus atom results in a decrease in the degree of P-N bond cleavage. The primary and secondary diphenylphosphinic amides containing a β-hydroxyethyl group at the nitrogen atom are extremely unstable under the alkaline conditions and are converted quantitatively to the diphenylphosphinic acid salt.
- Bondarenko,Kharlamov,Vendilo
-
experimental part
p. 1872 - 1885
(2011/01/06)
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- PROCESS FOR OBTAINING AMINES BY REDUCTION OF AMIDES
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Disclosed is a process for the preparation of primary, secondary and tertiary amines via a catalytic hydrogenation of unsubstituted, N- substituted, and N,N- disubstituted amides. The amide is led, together with an auxiliary amine, in vaporised form in a hydrogen containing gas flow over the catalyst. The process can be carried out at relatively low pressures, between 2 and 50 bars, using typical hydrogenation catalysts like CuCr-type catalysts. The amine is obtained with high yield and high selectivity. The process can be carried out in a continuous fixed bed reactor.
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Page/Page column 12
(2008/06/13)
-
- Process for obtaining amines by reduction of amides
-
Disclosed is a process for the preparation of primary, secondary and tertiary amines via a catalytic hydrogenation of unsubstituted, N-substituted, and N,N-disubstituted amides. The amide is led, together with an auxiliary amine, in vaporised form in a hydrogen containing gas flow over the catalyst. The process can be carried out at relatively low pressures, between 2 and 50 bars, using typical hydrogenation catalysts like CuCr-type catalysts. The amine is obtained with high yield and high selectivity. The process can be carried out in a continuous fixed bed reactor.
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Page/Page column 4,5
(2008/06/13)
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- Process for obtaining amines by reduction of amides
-
Disclosed is a process for the preparation of primary, secondary and tertiary amines via a catalytic hydrogenation of unsubstituted, N-substituted, and N,N- disubstituted amides. The amide is led, together with an auxiliary amine, in vaporised form in a hydrogen containing gas flow over the catalyst. The process can be carried out at relatively low pressures, between 2 and 50 bars, using typical hydrogenation catalysts like CuCr-type catalysts. The amine is obtained with high yield and high selectivity. The process can be carried out in a continuous fixed bed reactor.
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Page/Page column 8
(2008/06/13)
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- Ind2TiMe2-catalyzed addition of methyl- and ethylamine to alkynes
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We describe a very simple hydrogenation-like experimental protocol for the addition of gaseous methyl- and ethylamine to alkynes in the presence of Ind2TiMe2 as the catalyst. For efficient hydroamination reactions it is sufficient to stir a mixture of the alkyne and the catalyst in toluene at temperatures between 80°C (terminal alkynes) and 105°C (internal alkynes) under a constant pressure of 1 atm of the corresponding amine. After subsequent reduction of the initially formed imines, methyl- and ethylamine derivatives are the final products of the described one-pot reaction sequences. In the case of 2-alkyl-1-phenylalkynes as starting materials, biologically interesting 2-phenylethylamine derivatives possessing a small methyl or ethyl substituent at the N atom are easily accessible by the new reaction protocol. Wiley-VCH Verlag GmbH & Co. KGaA, 2005.
- Marcsekova, Klaudia,Wegener, Bernd,Doye, Sven
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p. 4843 - 4851
(2007/10/03)
-
- Cesium effect: High chemoselectivity in direct N-alkylation of amines
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A novel method for the mono-N-alkylation of primary amines, diamines, and polyamines was developed using cesium bases in order to prepare secondary amines efficiently. A cesium base not only promoted alkylation of primary amines but also suppressed overalkylations of the produced secondary amines. Various amines, alkyl bromides, and alkyl sulfonates were examined, and the results demonstrated this methodology was highly chemoselective to favor mono-N-alkylation over dialkylation. In particular, use of either sterically demanding substrates or amino acid derivatives afforded the secondary amines exclusively, offering wide applications in peptidomimetic syntheses.
- Salvatore, Ralph Nicholas,Nagle, Advait S.,Kyung, Woon Jung
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p. 674 - 683
(2007/10/03)
-
- Butyltriphenylphosphonium tetraborate (BTPPTB) as a selective reducing agent for the reduction of imines, enamines and oximes and reductive alkylation of aldehydes or ketones with primary amines in methanol or under solid-phase conditions
-
Butyltriphenylphosphonium tetraborate (BTPPTB) 1, generated as white solid from butyltriphenylphosphonium bromide and sodium borohydride, is found to be a selective and versatile reducing agent. The reagent in methanol or under solvent-free conditions is very useful for the reduction of imines, enamines and oximes or reductive amination of aldehydes and ketones. Under solvent-free conditions the reactions are faster and the yields of the products are higher.
- Hajipour,Mohammadpoor-Baltork,Noroallhi
-
p. 152 - 156
(2007/10/03)
-
- Zwitterionic sulfobetaine inhibitors of squalene synthase
-
A substantial number of sulfobetaines (e.g., 10) have been synthesized and evaluated as inhibitors of squalene synthase (SS) on the basis of the idea that their zwitterionic structure would have properties conducive both to binding in the active site and to passage through cell membranes. When the simple sulfobetaine moiety is incorporated into compounds containing hydrophobic portions like those in farnesyl diphosphate (1) or presqualene diphosphate (2), inhibition of SS in a rat liver microsomal assay was indeed observed. For example, farnesylated sulfobetaine 10 has IC50 = 10 μM and aromatic derivative 35 has IC50 = 2 μM for SS inhibition. A wide variety of structural modifications, exemplified by compounds 43, 52, 76, 85, 91, 99, 111, and 115, was investigated. Unfortunately, no inhibitors in the submicromolar range were discovered, and exploration of a different type of zwitterion seems necessary if this appealing approach to inhibition of SS is going to provide a potential antihypercholesterolemic agent.
- Spencer, Thomas A.,Onofrey, Thomas J.,Cann, Reginald O.,Russel, Jonathon S.,Lee, Laura E.,Blanchard, Daniel E.,Castro, Alfredo,Gu, Peide,Jiang, Guojian,Shechter, Ishaiahu
-
p. 807 - 818
(2007/10/03)
-
- Preparation de nouveaux β-aminoacides a longue chaine et leur conversion en carboxybetaines bicatenaires F-alkylees
-
The synthesis of amphoteric F-alkylated bitailed surfactants derived from new β-aminoacid intermediates is described. N-alkyl N-benzyl amines or N-alkyl N-methyl amines are added to acrylic acid. The β-amino acids obtained are quaternized by 2-F-alkyl ethyl acetates or thioacetate bromides to produce the F-alkylated double-chain carboxybetaines.
- Enjalbert,Bassilana,Krier,Szoenyi,Cambon
-
p. 145 - 152
(2007/10/03)
-
- Diesters of carbonic acid endowed with antiviral and anti-inflammatory activity
-
Diesters of carbonic acid disubstituted with primary, secondary or tertiary amine groups, pharmaceutically acceptable salts thereof, and their use as antiviral and inti-inflammatory agents.
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-
- Lithium aluminum hydride-N-methylpyrrolidine complex. 1 Synthesis and reactivity of lithium aluminum hydride-N-methylpyrrolidine complex. An air and thermally stable reducing agent derived from lithium aluminum hydride
-
A 1:1 lithium aluminum hydride-N-methylpyrrolidine complex (LAHNMP), obtained by the reaction of lithium aluminum hydride with N-methylpyrrolidine, is a powerful reducing agent, comparable to lithium aluminum hydride in its reducing properties. LAHNMP reduces esters, lactones, anhydrides and carboxylic acids to the corresponding alcohols. Test reductions show that LAHNMP also reduces a wide range of functional groups, including amides, epoxides, oximes, nitriles, nitro compounds and halides. LAHNMP can be safely transferred in air with the use of a plastic spatula and used in an open container without the need for an inert atmosphere, provided that hydrogen is not evolved during the reduction.
- Fuller,Stangeland,Jackson,Singaram
-
p. 1515 - 1518
(2007/10/02)
-
- Selectivity control in substituted fatty amines synthesis from esters or nitriles in the presence of bifunctional catalysts
-
Copper chromite-type catalysts, supported by alumina or graphite and promoted with barium, were used for the one-step synthesis of tertiary fatty amines [R2NCH3 or RN(CH3)2] from ester, acid or nitrile and ammonia, methanol and hydrogen. The surface composition of the catalysts, studied by X-ray photoelectron spectroscopy and by adsorption experiments, showed that there was a correlation between selectivity and the presence of a well-dispersed CuCrO2 phase, stabilized with barium. Moreover, the elements influencing the stability of the copper catalysts were also studied, and the promoter or/and the support increased the copper surface area and the stability of the catalyst in the presence of water or ammonia.
- Barrault,Brunet,Suppo-Essayem,Piccirilli,Guimon
-
p. 1231 - 1238
(2007/10/02)
-
- Effect of the N-Methylation of Dodecylammonium Chloride on the Adsorption from Its Micellar Solution
-
The surface tension of the aqueous solution of dodecylmethylammonium chloride (DMAC) and dodecyldimethylammonium chloride (DDAC) was measured as a function of temperature under atmospheric pressure at concentrations below and above the critical micelle concentration (cmc).The entropy and energy of adsorption from the monomeric state in the aqueous solution and the micellar state were evaluated by applying the thermodynamic equations of adsorption to the surface tension values.The thermodynamic quantities were compared with those of the aqueous solutions of dodecylammonium chloride (DAC) and dodecyltrimethylammonium chloride (DTAC).It was found that the successive N-methylation of DAC has a considerable effect on the adsorbed film with changes in its surface density, entropy, and energy brought about by changes in the geometry and the hydrophilicity of the polar head group.
- Aratono, Makoto,Okamoto, Toru,Ikeda, Norihiro,Motomura, Kinsi
-
p. 2773 - 2778
(2007/10/02)
-
- N-Monomethylation of Primary Amines via Intermediate Benzothiazol-2(3H)-imines
-
Aliphatic and aromatic amines are converted by successive treatment with (i) 3-methyl-2-methylthiobenzothiazolium iodide, (ii) methyl iodide or toluene-p-sulphonate, and (iii) butylamine, in high yield under mild conditions into their mono-N-methyl derivatives.
- Katritzky, Alan R.,Drewniak, Malgorzata,Aurrecoechea, Jose M.
-
p. 2539 - 2542
(2007/10/02)
-
- A New and Specific Method for the Monomethylation of Primary Amines
-
The reduction of monomeric methyleneamines, representing a convenient and highly specific procedure for the title reaction, is studied.
- Barluenga, Jose,Bayon, Ana M.,Asensio, Gregorio
-
p. 1334 - 1335
(2007/10/02)
-
- Process for preparing alkyldimethylamines
-
A process for preparing alkyldimethylamines which comprises passing through a fixed bed, containing a copper catalyst, optionally chromium oxide, and an oxide of a Group I metal, selected amounts of dimethylamine and an alcohol or mixtures of alcohols.
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