871-71-6Relevant articles and documents
CeO2-catalyzed direct synthesis of dialkylureas from CO2 and amines
Tamura, Masazumi,Ito, Kazuki,Nakagawa, Yoshinao,Tomishige, Keiichi
, p. 75 - 85 (2016/11/11)
CeO2 showed higher activity for the direct synthesis of 1,3-dibutylurea (DBU) from CO2 and n-butylamine than the metal oxides tested. The solvent largely influenced the reaction over CeO2, and N-methylpyrrolidone (NMP) was preferable among various solvents tested from the viewpoints of activity and selectivity. The catalyst system composed of CeO2 catalyst and NMP solvent (CeO2 in NMP) was applicable to the reactions of various amines such as linear primary alkylamines or branched primary alkylamines, although tert-butylamine afforded low conversion. In contrast, secondary amines and aniline provided no yield of the ureas. The combination of 2-cyanopyridine with CeO2 in NMP (CeO2 in NMP with 2-cyanopyridine) promoted the transformation of the unreactive amines, showing that tert-butylamine and aniline were converted to the corresponding ureas in 82% and 80% yields, respectively. These yields are much higher than those reported in the previous literatures, indicating that CeO2 in NMP with 2-cyanopyridine drastically promoted transformation of amines with low reactivity.
Copper(I)-Catalysed Multicomponent Reaction: Straightforward Access to 5-Hydroxy-1H-pyrrol-2(5H)-ones
Mardjan, Muhammad Idham Darussalam,Parrain, Jean-Luc,Commeiras, Laurent
, p. 543 - 548 (2016/02/27)
A copper-catalysed multicomponent coupling reaction between readily available (Z)-3-iodoacrylic acids, terminal alkynes, and primary amines was developed to smoothly access a small library of 5-hydroxy-1H-pyrrol-2(5H)-ones in good yields. This practical and general process was applied to a short-steps synthesis of the natural product pulchellalactam.
Selective N-methylation of aliphatic amines with CO2 and hydrosilanes using nickel-phosphine catalysts
Gonzlez-Sebastin, Lucero,Flores-Alamo, Marcos,Garca, Juventino J.
, p. 763 - 769 (2015/05/12)
A method using CO2 and PhSiH3 for the methylation of primary and secondary aliphatic amines catalyzed by Ni (0) complexes was developed, selectively producing the monomethylated products in moderate to good yields. For that purpose, two catalysts were used: [(dippe)Ni(μ-H)]2 and the commercially available Ni(COD)2/dcype, both of which were rather efficient in this process. With a slight experimental modification, the reaction allowed the production of monomethylated ureas in good yields by using low amounts of PhSiH3. On the basis of the experimental results, we propose a possible reaction mechanism for the formation of the new C-N bond.