4559-92-6Relevant articles and documents
Broad Scope and High-Yield Access to Unsymmetrical Acyclic [11C]Ureas for Biomedical Imaging from [11C]Carbonyl Difluoride
Jakobsson, Jimmy E.,Jana, Susovan,Lu, Shuiyu,Pike, Victor W.,Telu, Sanjay
supporting information, p. 10369 - 10376 (2021/06/07)
Effective methods are needed for labelling acyclic ureas with carbon-11 (t1/2=20.4 min) as potential radiotracers for biomedical imaging with positron emission tomography (PET). Herein, we describe the rapid and high-yield syntheses of unsymmet
Visible-light-promoted oxidative desulphurisation: A strategy for the preparation of unsymmetrical ureas from isothiocyanates and amines using molecular oxygen
Deng, Weiseng,Gan, Ziyu,Jiang, Yuan-Ye,Li, Guoqing,Yan, Qiuli,Yang, Daoshan
supporting information, p. 2956 - 2962 (2020/06/17)
A green and efficient visible-light promoted oxidative desulphurisation protocol has been proposed for the construction of unsymmetrical ureas under mild conditions with broad substrate scope and good functional group tolerance. Most appealingly, the reaction can proceed smoothly without adding any strong oxidants. Control experiments and computational studies support a mechanism involving water-assisted in situ generation of thioureas and photocatalytic oxidative desulphurisation. The present method provides a promising synthesis strategy for the formation of diverse and useful unsymmetrical urea derivatives in the fields of pharmaceutical and synthetic chemistry.
Method for preparing asymmetric urea compound (by machine translation)
-
Paragraph 0043-0048, (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)