- Methoxycarbonylation of Alkyl-, Cycloalkyl-, and Arylamines with Dimethyl Carbonate in the Presence of Binder-Free Zeolite
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Abstract: Methyl N-alkyl-, N-cycloalkyl-, and N-arylcarbamates were synthesized by reaction of the correspondingamines with dimethyl carbonate in the presence of binder-free FeHY zeolite. Theoptimal conditions (reactant ratio, amount of the catalyst, temperature,reaction time) were found to afford the target products with high yields.
- Khazipova, A. N.,Khusnutdinov, R. I.,Mayakova, Yu. Yu.,Shchadneva, N. A.
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p. 1228 - 1235
(2020/10/02)
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- CeO2-catalyzed direct synthesis of dialkylureas from CO2 and amines
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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.
- Tamura, Masazumi,Ito, Kazuki,Nakagawa, Yoshinao,Tomishige, Keiichi
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- Synthesis of carbamates from amines and dialkyl carbonates: Influence of leaving and entering groups
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A number of carbamates were synthesised through a halogen-free process by reacting amines with symmetrical and unsymmetrical carbonates. The results obtained showed a specific trend of preferred leaving groups (in the dialkyl carbonates) depending on whether a catalyst or a base was used. On the other hand, investigations conducted on the preferred entering groups (amines) for the synthesis of carbamates showed the same trend regardless of whether a catalyst or a base was used. Finally, in accordance with the results obtained, it was possible to synthesise sterically hindered carbamates in high yield by transesterification of methyl carbamate with a sterically hindered alcohol. Georg Thieme Verlag Stuttgart New York.
- Tundo, Pietro,McElroy, C. Robert,Aricò, Fabio
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experimental part
p. 1567 - 1571
(2010/09/05)
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- Reactivity of mono- and di-methoxycarbonyl complexes of PdII towards amines and copper amine complexes: role of copper in the catalyzed palladium-copper oxidative carbonylation of amines
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The reactivity of mono- and di-methoxycarbonyl complexes of palladium of formula (n = 1 or 2; L2 = chelating ligand) towards amines in the presence of Cl or CuCl2 has been studied.The reactions yield N,N'-disubstituted ureas or carbamates, respectively.These results are compared with the dioxygen-induced carbonylative oxidation of amines catalyzed by palladium-based systems. Key words: Palladium; Copper; Carbonylation; Amine; Urea; Carbamate
- Giannoccaro, Potenzo
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p. 249 - 252
(2007/10/02)
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- A Novel Catalytic Synthesis of Carbamates by the Oxidative Alkoxycarbonylation of Amines in the Presence of Platinum Group Metal and Alkali Metal Halide or Onium Halide
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Carbamates are prepared in good yields from amines, alcohols, CO, and oxygen in the presence of a novel catalyst system comprising platinum group metal and iodide.
- Fukuoka, Shinsuke,Chono, Masazumi,Kohno, Masashi
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p. 1458 - 1460
(2007/10/02)
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- ACETOXYLATION OF PIPERIDINE DERIVATIVES AT THE 3-POSITION. STEREOSELECTIVE SYNTHESIS OF PSEUDOCONHYDRINE AND N-METHYLPSEUDOCONHYDRINE
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Anodic oxidation of N-methoxycarbonylpipridine derivatives in AcOH gave 2,3-diacetoxylated products, which were shown to be useful intermediates for the stereoselective synthesis of 3-hydroxypiperidine derivatives including pseudoconhydrine and N-methylpseudoconhydrine, the Conium alcaloids.
- Shono, Tatsuya,Matsumura, Yoshihiro,Onomura, Osamu,Kanazawa, Takenobu,Habuka, Masahiro
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p. 1101 - 1104
(2007/10/02)
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- REACTION OF ACTIVATED AZIRIDINES WITH AMINES
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The reactions of 1-alkoxycarbonylaziridines, 1-(phenylaminocarbonyl)aziridine, and 1-arylsulfonylaziridines with ammonia and amines were investigated.It was shown that the opening of the aziridine ring in a number of cases is accompanied by aminolysis of the alkoxycarbonyl group.The dependence of the ratio of ring opening and aminolysis products on the structure of the amines is discussed.
- Baranov, S. V.,Mochalin V. B.
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p. 951 - 953
(2007/10/02)
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