- Ultra-small cobalt nanoparticles from molecularly-defined Co-salen complexes for catalytic synthesis of amines
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We report the synthesis of in situ generated cobalt nanoparticles from molecularly defined complexes as efficient and selective catalysts for reductive amination reactions. In the presence of ammonia and hydrogen, cobalt-salen complexes such as cobalt(ii)-N,N′-bis(salicylidene)-1,2-phenylenediamine produce ultra-small (2-4 nm) cobalt-nanoparticles embedded in a carbon-nitrogen framework. The resulting materials constitute stable, reusable and magnetically separable catalysts, which enable the synthesis of linear and branched benzylic, heterocyclic and aliphatic primary amines from carbonyl compounds and ammonia. The isolated nanoparticles also represent excellent catalysts for the synthesis of primary, secondary as well as tertiary amines including biologically relevant N-methyl amines.
- Beller, Matthias,Chandrashekhar, Vishwas G.,Gawande, Manoj B.,Jagadeesh, Rajenahally V.,Kalevaru, Narayana V.,Kamer, Paul C. J.,Senthamarai, Thirusangumurugan,Zbo?il, Radek
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p. 2973 - 2981
(2020/03/27)
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- Synthesis of N-Substituted phosphoramidic acid esters as “reverse” fosmidomycin analogues
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An efficient synthetic pathway to a series of novel “reverse” fosmidomycin analogues has been developed, commencing from substituted benzylamines. In these analogues, the fosmidomycin hydroxamate moiety is reversed and the tetrahedral methylene carbon adjacent to the phosphonate moiety is replaced by a nitrogen atom bearing different benzyl groups. The resulting phosphonate esters were designed as potential antimalarial “pro-drugs”.
- Adeyemi, Christiana M.,Hoppe, Heinrich C.,Isaacs, Michelle,Klein, Rosalyn,Lobb, Kevin A.,Kaye, Perry T.
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p. 2371 - 2378
(2019/03/23)
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- A benzylamine synthetic method of the compound (by machine translation)
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The invention discloses a compound of formula (V) indicated by the benzylamine compound synthetic methods: shown in formula (IV) of the phenmethyl nitrine as raw materials, in the boron tribromide, solvent A and gas B under the protection of the reduction reaction, after the reaction, the solvent C quenching, after treatment [...] (V) indicated by the benzylamine compound. Compared with the existing method, the invention adopts the mild reaction conditions of boron tribromide reagent, avoid the use of a metal catalyst, the operation is simple, the reaction yield is high. (by machine translation)
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Paragraph 0044; 0045; 0046
(2018/09/11)
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- Chemo-selective reduction of nitro and nitrile compounds using Ni nanoparticles immobilized on hyperbranched polymer-functionalized magnetic nanoparticles
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The nitro and nitrile groups in aromatic and aliphatic compounds containing various reducible substituents such as carboxylic acid, ketone, aldehyde and halogen are selectively reduced to the corresponding amines in water as a green solvent with excellent yields by employing NaBH4 in the presence of Fe3O4@PAMAM/Ni(0)-b-PEG nanocatalyst. The morphology and structural features of the catalyst were characterized using various microscopic and spectroscopic techniques. The designed catalyst system because of it being covered with hydrophilic polymers is soluble in a wide range of solvents (e.g. water and ethanol) and suitable for immobilizing and stabilizing Ni nanoparticles in aqueous mediums. In addition, the catalyst can be easily recovered from a reaction mixture by applying an external magnetic field and can be reused up to six runs without significant loss of activity.
- Tabatabaei Rezaei, Seyed Jamal,Mashhadi Malekzadeh, Asemeh,Poulaei, Sima,Ramazani, Ali,Khorramabadi, Hossein
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- Versatile Dynamic Covalent Assemblies for Probing π-Stacking and Chirality Induction from Homotopic Faces
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Herein we report for the first time the use of dynamic covalent reactions (DCRs) for building a π-stacking model system and further quantifying its substituent effects (SEs), which remain a topic of debate despite the rich history of stacking. A general DCR between 10-methylacridinium ion and primary amines was discovered, in which π-stacking played a stabilizing role. Facile quantification of SEs with in situ competing π-stacking systems was next achieved in the form of amine exchange exhibiting structural diversity by simply varying components. The linear correlation with σm in Hammett plots indicates the dominance of purely electrostatic SEs, and the additivity of SEs is in line with the direct interaction model. With α-chiral amines π-stacking within the adduct enabled chirality transfer from homotopic faces. The strategy of dynamic covalent assembly should be appealing to future research of probing weak interactions and manipulating chirality.
- Ye, Hebo,Hai, Yu,Ren, Yulong,You, Lei
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supporting information
p. 3804 - 3809
(2017/03/27)
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- MOF-derived cobalt nanoparticles catalyze a general synthesis of amines
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The development of base metal catalysts for the synthesis of pharmaceutically relevant compounds remains an important goal of chemical research. Here, we report that cobalt nanoparticles encapsulated by a graphitic shell are broadly effective reductive amination catalysts. Their convenient and practical preparation entailed template assembly of cobaltdiamine- dicarboxylic acid metal organic frameworks on carbon and subsequent pyrolysis under inert atmosphere.The resulting stable and reusable catalysts were active for synthesis of primary, secondary, tertiary, and N-methylamines (more than 140 examples).The reaction couples easily accessible carbonyl compounds (aldehydes and ketones) with ammonia, amines, or nitro compounds, and molecular hydrogen under industrially viable and scalable conditions, offering cost-effective access to numerous amines, amino acid derivatives, and more complex drug targets.
- Jagadeesh, Rajenahally V.,Murugesan, Kathiravan,Alshammari, Ahmad S.,Neumann, Helfried,Pohl, Marga-Martina,Radnik, J?rg,Beller, Matthias
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p. 326 - 332
(2017/09/28)
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- A method for the production of primary amines
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The invention relates to the field of chemical industry and particularly relates to a method for preparing primary amine by using the raw materials including halogenated hydrocarbon (or hydrocarbon alcohol sulfonate) and ammonia water (or formamide). The method comprises the following three steps: (1) imidization: 3,4-diarylfuran-2,5-diketone (I) reacts with ammonia (or formamide) and the like to obtain 3,4-diaryl-1H-pyrrole-2,5-diketone (II); (2) N-hydrocarbylation: 3,4-diaryl-1H-pyrrole-2,5-diketone (II) generates an N-hydrocarbylation reaction with halogenated hydrocarbon (or hydrocarbon alcohol sulfonate) in the presence of alkali to obtain N-hydrocarbyl-3,4-diaryl-1H-pyrrole-2,5-diketone (III); and (3) hydrolysis: N-hydrocarbyl-3,4-diaryl-1H-pyrrole-2,5-diketone (III) is subjected to alkali hydrolysis to obtain primary amine and the generated 2,3-diaryl maleate is subjected to acid treatment and automatic ring closing to form 3,4-diaryl furan-2,5-diketone (I) which is subjected to imidization and directly applied to the N-hydrocarbylation reaction. The method provided by the invention has the characteristics that the 3,4-diaryl furan-2,5-diketone can be circularly used at a high recovery rate, the molar ratio of the raw materials is low, and the yield of the product primary amine is high.
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Paragraph 0237; 0287
(2016/10/09)
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- THIENOPYRIMIDINES
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Thienopyrimidines of the formula (I) and their physiologically acceptable salts, in which R1, R2 and X are as defined in claim 1, exhibit phosphodiesterase V inhibition and can be employed for the treatment of illnesses of the cardiovascular system and for the treatment and/or therapy of impotence.
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- 2-aminobenzoxazole derivatives and combinatorial libraries thereof
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The present invention relates to novel 2-aminobenzoxazole derivative compounds of the following formula: wherein R1 to R4 and Z have the meanings provided herein. The invention further relates to combinatorial libraries containing two or more such compounds, as well as methods of preparing 2-aminobenzoxazole derivative compounds.
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- Benzylamines: Synthesis and evaluation of antimycobacterial properties
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The synthesis of benzylamines with various N-alkyl chains and substituents in the aromatic system as well as their evaluation on Mycobacterium tuberculosis H 37 Ra are described. The most active compounds in this test, N-methyl-3-chlorobenzylamine (MIC 10.2 μg/mL), N-methyl-3,5-dichlorobenzylamine (93, MIC 10.2 μg/mL), and N-butyl-3,5-difluorobenzylamine (MIC 6.4 μg/mL), also exhibited a marked inhibitory effect on Mycobacterium marinum and Mycobacterium lufu used for the determination of antileprotic properties. The combination of 93 with aminosalicylic acid, streptomycin, or dapsone exert marked supra-additive effects on M. tuberculosis H 37 Ra.
- Meindl,Von Angerer,Schonenberger,Ruckdeschel
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p. 1111 - 1118
(2007/10/02)
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