1055-79-4Relevant academic research and scientific papers
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 0049-0055, (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.
Pd(OAc)2-catalyzed carbonylation of amines
Orito, Kazuhiko,Miyazawa, Mamoru,Nakamura, Takatoshi,Horibata, Akiyoshi,Ushito, Harumi,Nagasaki, Hideo,Yuguchi, Motoki,Yamashita, Satoshi,Yamazaki, Tetsuro,Tokuda, Masao
, p. 5951 - 5958 (2007/10/03)
A phosphine-free catalytic system [Pd(OAc)2-Cu(OAc) 2-air] induced a substrate-specific carbonylation of amines in boiling toluene under CO gas (1 atm). Symmetrical N,N′-dialkylureas were obtained by the carbonylation of primary amines. N,N,N′-Trialkylureas were selectively formed by addition of a secondary amine to the above reaction vessel. Secondary amines did not give tetraalkylureas. However, dialkylamines with a phenyl group on their alkyl chains, such as N-monoalkylated benzylic amine or phenethylamine derivatives, underwent a direct aromatic carbonylation to afford five- or six-membered benzolactams. In the carbonylation, the chelation effect or steric repulsion between Pd(II) and the meta-substituent in the ortho-palladation and the ring sizes of cyclopalladation products that were formed prior to carbonylation were found to generate good site selectivity and increase the reaction rate. In contrast, carbonylation of ω- arylalkylamines with a hydroxyl group gave neither ureas nor benzolactams but instead produced 1,3-oxazolidinones smoothly. Hydrochlorides of amines also underwent carbonylation to afford the corresponding amides under the conditions used. This procedure made it possible to prepare ureas of amino acid esters and N-alkylcarbamates in practical yields.
