- Oxidative carbonylation of aliphatic amines catalysed by nickel-complexes
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The catalytic activity of some nickel-complexes in the dioxygen-induced oxidative carbonylation of amines has been studied.N,N'-substituted ureas were obtained in fairly low yields (maximum 55percent), instead of N,N'-oxamides expected on the basis of a p
- Giannoccaro, Potenzo,Nobile, Cosimo Francesco,Mastrorilli, Pietro,Ravasio, Nicoletta
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- CO-use CO2 Method for synthesizing N, N - dialkyl oxalate
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The invention provides a method for synthesizing N,N-dialkyl oxamide by using CO2. According to the method, in an organic or inorganic solvent, one-step synthetic reaction is performed on the CO2 and organic amine to synthesize the N,N-dialkyl oxamide, with N,N-dialkyl urea and water as byproducts, in the presence of a certain catalyst and under a certain reaction condition that the reaction pressure is 10-80atm and the reaction temperature is 100-200 DEG C. The invention discloses the method for synthesizing the N,N-dialkyl oxamide by using the CO2. According to the method, a valuable and toxic metal catalyst and a toxic and explosive gas in the prior art are not used, and reactants, products, and added components in a system are safe and environment-friendly; the yield is considerable; technically, an improvement room exists; a safe and environment-friendly new method is provided for preparing the N,N-dialkyl oxamide.
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Paragraph 0027; 0028; 0029; 0030; 0031
(2016/11/17)
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- Catalytic Oxidative Carbonylation of Amino Moieties to Ureas, Oxamides, 2-Oxazolidinones, and Benzoxazolones
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The direct syntheses of ureas, oxamides, 2-oxazolidinones, and benzoxazolones by the oxidative carbonylation of amines, β-amino alcohols, and 2-aminophenols allows us to obtain high value added molecules, which have a large number of important applications in several fields, from very simple building blocks. We have found that it is possible to perform these transformations using the PdI2/KI catalytic system in an ionic liquid, such as 1-butyl-3-methylimidazolium tetrafluoroborate, as the solvent, the solvent/catalyst system can be recycled several times with only a slight loss of activity, and the product can be recovered easily by crystallization.
- Mancuso, Raffaella,Raut, Dnyaneshwar S.,Della Ca, Nicola,Fini, Francesco,Carfagna, Carla,Gabriele, Bartolo
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p. 2204 - 2211
(2015/07/15)
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- Efficient synthesis of ureas by direct palladium-catalyzed oxidative carbonylation of amines
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A general synthesis of symmetrically disubstituted ureas and trisubstituted ureas by direct Pd-catalyzed oxidative carbonylation of primary amines or of a mixture of a primary and a secondary amine, respectively, with unprecedented catalytic efficiencies for this kind of process, is reported. Reactions are carried out at 90-100 °C in DME as the solvent in the presence of PdI 2 in conjunction with an excess of KI as the catalytic system and under 20 atm of a 4:1 mixture of CO and air. In some cases, working in the presence of an excess of CO2 (40 atm) in addition to CO and air (60 atm total) had a beneficial effect on substrate reactivity and product yield. Cyclic five-membered and six-membered ureas were easily formed from primary diamines. The methodology has been successfully applied to the synthesis of pharmacologically active ureas, such as those deriving from α-amino esters or urea NPY5RA-972, a potent antagonist of the neuropeptide Y5 receptor.
- Gabriele, Bartolo,Salerno, Giuseppe,Mancuso, Raffaella,Costa, Mirco
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p. 4741 - 4750
(2007/10/03)
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- Selective and environmentally friendly methodologies based on the use of electrochemistry for fine chemical preparation: An efficient synthesis of N,N′-disubstituted ureas
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A novel efficient synthesis of N,N′-disubstituted ureas has been developed. Aromatic and aliphatic primary amines undergo oxidative carbonylation under atmospheric pressure of carbon monoxide using Pd(II) catalyst in combination with its anodic recycling at a graphite electrode.
- Chiarotto, Isabella,Feroci, Marta
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p. 7137 - 7139
(2007/10/03)
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- A novel ZrO2-SO42- supported palladium catalyst for syntheses of disubstituted ureas from amines by oxidative carbonylation
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The syntheses of disubstituted ureas by carbonylation of a series of amines in the presence of a sulfate modified zirconia supported palladium catalyst was investigated at an initial total pressure of 4.0 MPa and 135°C. High conversions and yields were achieved for the synthesis of symmetric dialkylureas. This supported catalyst could also be easily separated and recovered after reaction.
- Shi, Feng,Deng, Youquan,SiMa, Tianlong,Yang, Hongzhou
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p. 2161 - 2163
(2007/10/03)
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- Reactivity of Carbamoyl Radicals. A New, General, Convenient Free-Radical Synthesis of Isocyanates from Monoamides of Oxalic Acid
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A new, general, simple synthesis of isocyanates was developed by oxidation of monoamides of oxalix acid with peroxydisulfate catalyzed by Ag and Cu salts.The reaction was carried out in a two-phase system (water and an organic solvent), and it is suitable also for practical applications, due to the simple experimental conditions and the inexpensive as well as nontoxic reagents.The first example of homolytic intramolecular aromatic carbamoylation is also reported.
- Minisci, Francesco,Fontana, Francesca,Coppa, Fausta,Yan, Yong Ming
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p. 5430 - 5433
(2007/10/02)
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- Oxidative coupling of amines and carbon monoxide catalyzed by palladium complexes. Mono- and double carbonylation reactions promoted by iodine compounds.
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Iodine is an effective promoter for the carbonylation of primary and secondary amines to ureas using palladium acetate as the catalyst and a base (e.g.K2CO3) in acetonitrile (3 h at 95 deg C and 2.7 atm).Oxamides are formed in excellent yields when secondary amines are carbonylated in the presence of iodide ion and oxygen, while primary amines give ureas as the principal product at 95 deg C, and oxamide at room temperature.
- Pri-Bar, Ilan,Alper, Howard
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p. 1544 - 1547
(2007/10/02)
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- OXALSAEUREDERIVATE DURCH OXIDATIVE KUPPLUNG VON KOHLENMONOXID AN NICKEL
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Carbon monoxide is oxidatively coupled by ligand nickel(II) compounds with secondary, primary amines and with alkali alkoxides to give oxalic acid derivatives.In the case of secondary amines the CO coupling can be run catalytically by adding oxidants like copper(II) salts.The yield of oxalic esters depends on the types of ligands and anions.
- Hoberg, Heinz,Fananas, F. Javier,Riegel, Hans Josef
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p. 267 - 272
(2007/10/02)
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