5260-04-8Relevant articles and documents
Hydrosilane-Assisted Synthesis of Urea Derivatives from CO2and Amines
Zhao, Yulei,Guo, Xuqiang,Si, Zhiyao,Hu, Yanan,Sun, Ying,Liu, Yunlin,Ji, Zhongyin,You, Jinmao
, p. 13347 - 13353 (2020/11/02)
A methodology employing CO2, amines, and phenylsilane was discussed to access aryl- or alkyl-substituted urea derivatives. This procedure was characterized by adopting hydrosilane to promote the formation of ureas directly, without the need to prepare silylamines in advance. Control reactions suggested that FeCl3 was a favorable additive for the generation of ureas, and this 1,5,7-triazabicyclo[4.4.0]dec-5-ene-catalyzed reaction might proceed through nucleophilic addition, silicon migration, and the subsequent formal substitution of silylcarbamate.
Urea-based derivative and synthesis method thereof
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Paragraph 0056-0062, (2020/02/08)
The invention discloses a urea-based derivative and a synthesis method thereof. The synthesis method comprises: adding an amine-based catalyst into an amine-based compound used as a raw material, introducing carbon dioxide gas into a reaction bottle, sequentially adding a solvent, hydrosilane and a Lewis acid catalyst into the reaction bottle in the atmosphere of carbon dioxide gas, and carrying out a one-pot reaction to catalytically synthesize the urea-based derivative represented by a formula (I). According to the invention, the preparation method has advantages of mild reaction conditions,simple and easily available raw materials, simple and easily available amine-based catalyst, simple and easily available Lewis acid catalysts, good substrate universality, simple and convenient post-treatment, good yield and the like. The invention further discloses applications of the urea-based derivative represented by the formula (I) in the fields of synthesis and medicinal chemistry.
Synthesis of Urea Derivatives from CO2 and Silylamines
Xu, Maotong,Jupp, Andrew R.,Ong, Maegan S. E.,Burton, Katherine I.,Chitnis, Saurabh S.,Stephan, Douglas W.
supporting information, p. 5707 - 5711 (2019/04/16)
A series of thirty-three N,N′-diaryl, dialkyl, and alkyl-aryl ureas have been prepared in pyridine or toluene by reaction of silylamines with CO2. This protocol is shown to provide facile access to 13C-labeled ureas, as well as chiral and macrocyclic ureas. These reactions proceed through initial generation of the corresponding silylcarbamates, which subsequently react with silylamine under thermal conditions to afford the thermodynamically favored urea and disilyl ether.
The: Trans / cis photoisomerization in hydrogen bonded complexes with stability controlled by substituent effects: 3-(6-aminopyridin-3-yl)acrylate case study
Kwiatkowski, Adam,J?drzejewska, Beata,Józefowicz, Marek,Grela, Izabela,O?mia?owski, Borys
, p. 23698 - 23710 (2018/07/13)
The association of aminopyridine-based acrylic acid and its salt was studied by NMR titration experiments. The AA (acceptor, acceptor) hydrogen-bonding pattern present in the salt forms a complex readily with a DD (donor, donor) hydrogen-bonding pattern of the substituted ureas even in polar and competitive environment. The double carbon-carbon bond in the acrylic acid derivative is subjected to photoisomerization. This is dependent on the association with substituted urea derivatives. The substituent in ureas influences the trans/cis isomerization kinetics and position of the photostationary state. Two mechanisms that influence the photoisomerization were proposed. To the best of our knowledge, the trans/cis photoisomerization influenced by the substituent in such a hydrogen-bonding pattern has not observed previously. It was shown that interaction with urea derivatives causes lowering of the trans-to-cis photoreaction rates.
Stoichiometric Reactions of CO2 and Indium-Silylamides and Catalytic Synthesis of Ureas
Xu, Maotong,Jupp, Andrew R.,Stephan, Douglas W.
, p. 14277 - 14281 (2017/10/31)
The indium compounds In(N(SiMe3)2)2Cl?THF (2) and In(N(SiMe3)2)Cl2?(THF)n (3) were shown to react with CO2 to give [(Me3Si)2N)InX(μ-OSiMe3)]2 (X=N(SiMe3)2 4, Cl 5). 0.05–2.0 mol % of the species 3 acts as a pre-catalyst for the conversion of aryl and alkyl silylamines under CO2 (2–3 atm) to give the corresponding ureas in 70–99 % yields. A proposed mechanism is supported by experimental and computational data.
Urea-based constructs readily amplify and attenuate nonlinear optical activity in response to H-bonding and anion recognition
Asthana, Deepak,Pandey, Ravindra,Mukhopadhyay, Pritam
supporting information, p. 451 - 453 (2013/02/25)
Urea-based molecular constructs are shown for the first time to be nonlinear optically (NLO) active in solution. We demonstrate self-assembly triggered large amplification and specific anion recognition driven attenuation of the NLO activity. This orthogo
"Wurster-type" ureas as redox-active receptors for anions
Clare, John P.,Statnikov, Anna,Lynch, Vincent,Sargent, Andrew L.,Sibert, John W.
experimental part, p. 6637 - 6646 (2009/12/30)
(Chemical Equation Presented) Four redox-active receptors, 1-4, based on the incorporation of p-phenylenediamine(s) within a urea framework, were synthesized, and the affinities of two for a series of anions were quantified through UV-vis and NMR spectros
