61589-14-8Relevant academic research and scientific papers
The Origin of the Regioselectivity in the 2+2 Photochemical Cycloaddition Reactions of N-Benzoylindole with Alkenes: Trapping of 1,4-Biradical Intermediates with Hydrogen Selenide
Hastings, David J.,Weedon, Alan C.
, p. 4107 - 4110 (1991)
The 1,4-biradical species previously proposed as intermediates in the formation of cyclobutane adducts in the photochemical cycloaddition reaction between N-benzoylindole and alkenes have been trapped with hydrogen selenide.The structures of the trapped biradicals are consistent with the proposal that the first bond formed between the triplet excited state of the indole derivative and the alkenes is from the indole 2-position to that terminus of the alkene which is less able to stabilise a radical centre.This allows prediction of the reaction regiochemistry.Key Words: N-benzoylindole; photochemical cycloaddition; 1,4-biradicals; trapping.
Hydrosilane-Mediated Electrochemical Reduction of Amides
Okamoto, Kazuhiro,Nagahara, Shingo,Imada, Yasushi,Narita, Risako,Kitano, Yoshikazu,Chiba, Kazuhiro
, p. 15992 - 16000 (2021/07/20)
Electrochemical reduction of amides was achieved by using a hydrosilane without any toxic or expensive metals. The key reactive ketyl radical intermediate was generated by cathodic reduction. Continuous reaction with anodically generated silyl radicals or zinc bromide resulted in chemoselective deoxygenation to give the corresponding amines.
Manganese Catalyzed Direct Amidation of Esters with Amines
Fu, Zhengqiang,Wang, Xinghua,Tao, Sheng,Bu, Qingqing,Wei, Donghui,Liu, Ning
, p. 2339 - 2358 (2021/02/03)
The transition metal catalyzed amide bond forming reaction of esters with amines has been developed as an advanced approach for overcoming the shortcomings of traditional methods. The broad scope of substrates in transition metal catalyzed amidations remains a challenge. Here, a manganese(I)-catalyzed method for the direct synthesis of amides from a various number of esters and amines is reported with unprecedented substrate scope using a low catalyst loading. A wide range of aromatic, aliphatic, and heterocyclic esters, even in fatty acid esters, reacted with a diverse range of primary aryl amines, primary alkyl amines, and secondary alkyl amines to form amides. It is noteworthy that this approach provides the first example of the transition metal catalyzed amide bond forming reaction from fatty acid esters and amines. The acid-base mechanism for the manganese(I)-catalyzed direct amidation of esters with amines was elucidated by DFT calculations.
Frustrated Lewis Pair Catalyzed Hydrogenation of Amides: Halides as Active Lewis Base in the Metal-Free Hydrogen Activation
Sitte, Nikolai A.,Bursch, Markus,Grimme, Stefan,Paradies, Jan
supporting information, p. 159 - 162 (2019/01/04)
A method for the metal-free reduction of carboxylic amides using oxalyl chloride as an activating agent and hydrogen as the final reductant is introduced. The reaction proceeds via the hydrogen splitting by B(2,6-F2-C6H3)3 in combination with chloride as the Lewis base. Density functional theory calculations support the unprecedented role of halides as active Lewis base components in the frustrated Lewis pair mediated hydrogen activation. The reaction displays broad substrate scope for tertiary benzoic acid amides and α-branched carboxamides.
Methyl Esters as Cross-Coupling Electrophiles: Direct Synthesis of Amide Bonds
Zheng, Yan-Long,Newman, Stephen G.
, p. 4426 - 4433 (2019/05/08)
Amide bond formation and transition metal-catalyzed cross-coupling are two of the most frequently used chemical reactions in organic synthesis. Recently, an overlap between these two reaction families was identified when Pd and Ni catalysts were demonstrated to cleave the strong C-O bond present in esters via oxidative addition. When simple methyl and ethyl esters are used, this transformation provides a powerful alternative to classical amide bond formations, which commonly feature stoichiometric activating agents. Thus far, few redox-active catalysts have been demonstrated to activate the C(acyl)-O bond of alkyl esters, which makes it difficult to perform informed screening when a challenging reaction needs optimization. We demonstrate that Ni catalysts bearing diverse NHC, phosphine, and nitrogen-containing ligands can all be used to activate methyl esters and enable their use in direct amide bond formation.
Synthesis of Amides by Mild Palladium-Catalyzed Aminocarbonylation of Arylsilanes with Amines Enabled by Copper(II) Fluoride
Zhang, Jin,Hou, Yanyan,Ma, Yangmin,Szostak, Michal
, p. 338 - 345 (2019/01/10)
A general Pd-catalyzed synthesis of amides by oxidative aminocarbonylation of arylsilanes under mild conditions was accomplished for the first time. The reaction is promoted by a commercially available copper(II) fluoride, which acts as a dual silane activator and mild oxidant, enabling highly efficient aminocarbonylation of versatile arylsilanes at atmospheric CO pressure. The reaction is tolerant of a wide range of arylsilanes and various sensitive halide functional groups as well as a broad scope of amines are compatible with this oxidative process using cheap CO. A significant aspect involves the increased efficiency by the catalyst system. The reaction represents a segue into the powerful Pd-catalyzed oxidative transformations of organosilanes.
Secondary/tertiary amide compound and synthesis method thereof
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Paragraph 0171; 0172; 0173; 0174, (2019/01/21)
The invention discloses a secondary/tertiary amide compound and a synthesis method thereof. The method comprises the following steps: adding arylsilane and an amine compound, a catalyst and an additive to a solvent, introducing CO under a certain pressure, carrying out a carbonylation reaction, and carrying out separation and purification to obtain the secondary/tertiary amide. The method for preparing the secondary/tertiary amide by the carbonylation reaction has the advantages of concision, high efficiency, directness in the reaction, high atom economy, and wide sources and good stability ofa substrate. The reaction system of the invention does not require inert gas protection, and has mild conditions, and the target product is easy to separate and the yield reaches up to 92% under optimized reaction conditions.
Carbon bridged bis-amide-based rare-earth amine compound and its preparation and with [...][...] synthesis reaction in the application of the
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Paragraph 0124; 0125, (2019/04/02)
The invention discloses a carbon-bridged diacylamino rare earth amide with a general formula of {LLn[N(SiMe3)2]}2, wherein Ln is a rare earth metal selected from lanthanum, neodymium, samarium and yttrium, L represents a carbon-bridged diacylamino ligand, and n may be 1, 2 or 3 and can represent different ligands. The chemical structural formula of the carbon-bridged diacylamino rare earth amide differs with changes of the rare earth metal and the ligand. The invention targetedly discloses four chemical structural formulas of the rare earth amide as shown in the general formula. The carbon-bridged diacylamino rare earth amide provided by the invention is simple to synthesize, has definite structure and high yield and is easy to separate and purify. The invention also provides a preparation method for the rare earth amide and a method for applying the rare earth amide as a catalyst for catalysis of amidation of aldehyde and amine. The application method has the advantages of mild conditions, high activity, good selectivity, a wide substrate adaptation scope, a small catalyst amount and high product yield.
Intensified Microwave-Assisted N-Acylation Procedure - Synthesis and Activity Evaluation of TRPC3 Channel Agonists with a 1,3-Dihydro-2H-benzo[d]imidazol-2-one Core
Guedes de La Cruz, Gema,Svobodova, Barbora,Lichtenegger, Michaela,Tiapko, Oleksandra,Groschner, Klaus,Glasnov, Toma
, p. 695 - 700 (2017/03/21)
Upon controlled microwave heating and using cyanuric chloride as a coupling reagent, an efficient amidation procedure for the synthesis of 1,3-dihydro-2H-benzo[d]imidazol-2-one-based agonists of TRPC3/6 ion channels has been developed. Compared to the few conventional protocols, a drastic reduction in processing time from ca. 2 days down to 10 minutes was achieved accompanied by significantly improved product yields. The robustness of the method was confirmed by 18 additional examples including aromatic, aliphatic, and heterocyclic amines and acids. The obtained agonists were screened for biological activity at 1 μM concentration and few structure-activity relations have been established.
Synthesis and characterization of bridged bis(amidato) rare earth metal amides and their applications in C-N bond formation reactions
Zhao, Bei,Xiao, Yang,Yuan, Dan,Lu, Chengrong,Yao, Yingming
, p. 3880 - 3887 (2016/03/05)
Based on three bisamide proligands H2Ln (n = 1-3) (H2L1 = [(Me3C6H2CONHCH2)2CH2], H2L2 = [(Me3C6H2CONHCH2)2C(CH3)2], H2L3 = [Me3C6H2CONH(CH2)2]2NCH3), eight bis(amidato) trivalent rare-earth metal amides {LnRE[N(TMS)2]}2 (n = 1, RE = La (1), Sm (2), Nd (3), Y (4); n = 2, RE = La (5), Nd (6); n = 3, RE = La (7), Nd (8); TMS = SiMe3) were successfully synthesized by treatment of H2Ln with RE[N(TMS)2]3 in a 1:1 molar ratio. Complexes 3, and 5-8 were characterized by single-crystal X-ray diffraction, and NMR characterization was carried out for the La complexes 1, 5, 7 and the Y complex 4. These complexes exhibited high catalytic activities in both the direct amidation of aldehydes and the addition of amines with carbodiimine. It was found that the bis(amidato) rare earth metal amides bearing different linkers have different effects on the transformations and lanthanum and neodymium complexes performed better than others.
