555-37-3Relevant articles and documents
Method for preparing asymmetric urea compound (by machine translation)
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Paragraph 0043-0048; 0216-0221, (2020/03/25)
The invention provides a vehicle CO. 2 A method. for synthesizing an asymmetric urea compound by carbonylation coupling reaction of the carbonylation reagent is: and the aromatic, aliphatic primary amine compound and the aliphatic secondary amine compound and the normal pressure (100 °C, diglyme), can be efficiently prepared by using a common Lewis base and a hydrogen silane as the accelerator/CO under mild conditions. 2 The reaction produces a corresponding asymmetric urea compound. containing different functional groups, the process being operated at atmospheric pressure CO. 2 The use of an inexpensive Lewis base and, industrial silicon waste PMHS( for the green non-toxic carbonylation reagent) avoids toxic carbonylation reagents, high pressure, as an accelerator CO. 2 , The use, of the expensive dehydrating agent and the noble metal does not need to purify and separate the intermediate, and the pure product, is obtained by simple suction filtration separation after the reaction is ended . is a high efficiency, novel synthetic method . The commercial herbicide NEBURON. is successfully prepared by using the method. (by machine translation)
Assembly of N,N-disubstituted-N′-arylureas via a copper-catalyzed one-pot three-component reaction of aryl bromides, potassium cyanate, and secondary amines
Yin, Hongfei,Chen, Bing,Zhang, Xiaojing,Yang, Xinye,Zhang, Yihua,Jiang, Yongwen,Ma, Dawei
, p. 5326 - 5330 (2013/07/05)
A three-component reaction of aryl bromides, potassium cyanate, and secondary amines takes place at 110 C in MeCN under the catalysis of Cu 2O and 2-(2,6-dimethylphenylamino)-2-oxoacetic acid potassium salt, giving N,N-disubstituted-N′-arylurea
A novel synthesis of isocyanates and ureas via β-elimination of haloform
Braverman,Cherkinsky,Kedrova,Reiselman
, p. 3235 - 3238 (2007/10/03)
A novel synthesis of isocyanates via base-induced β-elimination of haloform from N-monosubstituted trihaloacetamides is described. The rate of reaction exhibits a strong dependence on the nature of the trihalomethyl group. Thus, while the reaction of tribromoacetamides proceeds at room temperature and the reaction of trichloroacetamides requires heating in polar solvents, no reaction could be observed for any of the corresponding trifluoro derivatives. This novel β-elimination of haloform from stable and readily available trihaloacetamides was applied to a 'one-pot' synthesis of ureas which avoids the use of phosgene and isolation of isocyanates.
