612-01-1Relevant articles and documents
Cp2TiCl2-CATALYZED REACTION OF GRIGNARD REAGENTS WITH ISOCYANATES, FORMATION OF REDUCTION-COUPLING PRODUCT OF ISOCYANATES
Zhang, Yongmin,Jiang, Jinlong,Zhang, Zhangxi
, p. 651 - 652 (1988)
Phenylisocyanate and phenylthioisocyanate react with Grignard reagents in the presence of a small amount of Cp2TiCl2 at room temperature to afford reduction-coupling products, N-methyl-N,N'-diphenylurea and N-methyl-N,N'-diphenylthiourea.
2,2,2-Trifluroenthanol promoted synthesis of unsymmetrical ureas from dioxazolones and amines via tandem lossen rearrangement/condensation process
Li, Jian,He, Wang,Lei, Pan,Song, Jiacheng,Huo, Jiyou,Wei, Hongbo,Bai, Hongjin,Xie, Weiqing
supporting information, p. 3590 - 3600 (2021/10/07)
A 2,2,2-trifluroenthanol (TFE) promoted synthesis of unsymmetric ureas was described. This approach enabled the construction of a variety of ureas from the readily prepared and easy-to-handle dioxazolones and amines via tandem Lossen rearrangement/condensation process. The reaction featured mild conditions for the urea synthesis under metal-free conditions, which was successively applied in the scale-up synthesis of herbicides Monuro and Isoproturon.
A Novel C–N Migration Rearrangement Based on N–F Compounds for the Synthesis of N-Alkyl Diaryl Ureas
Zhao, Yi-Xiao,Xie, Tian,Yang, San-Ke,Yang, Xian-Jin
, p. 437 - 445 (2020/01/22)
A novel rearrangement reaction based on the structure of N-fluoro-N-(phenylsulfonyl) benzamides (FPSBA) was developed. In the presence of base, unsymmetrical N-alkyl diaryl ureas were obtained in good yields which were accomplished through secondary alkyl phenylamines initiated 1,2-phenyl-shift migration rearrangement of N-fluoro-N-(phenylsulfonyl) benzamides. The reaction was carried out without using traditional, highly toxic reagents and noble metals. Whereas without rearrangement occurrence for primary phenylamines and aliphatic amines, normal amides and N-(phenylsulfonyl) benzamides were afforded respectively. Nitrene and phenyl isocyanate included process were prevented and a secondary alkyl phenylamine initiated vicinal SN2' reaction occurred. This rearrangement reaction features an interesting reaction mechanism, mild reaction conditions, simple operation, and useful products.