94398-06-8Relevant articles and documents
An Improved Synthesis of Urea Derivatives from N -Acylbenzotriazole via Curtius Rearrangement
Agrahari, Anand K.,Singh, Anoop S.,Singh, Sumit K.,Tiwari, Vinod K.,Yadav, Mangal S.
, p. 3443 - 3450 (2019/09/07)
The good leaving tendency of the benzotriazole moiety has been exploited for the synthesis of symmetric, unsymmetric, N -acyl, and cyclic ureas in good yields from N -acylbenzotriazoles by treating the latter with various amines in the presence of TMSN 3 /Et 3 N in a sealed tube. The salient features of the devised protocol includes the high-yield, mild, metal-free, one-pot reaction conditions, and short reaction time. Furthermore, in many cases, no column chromatography is required for the purification.
KINETICS AND MECHANISM OF METHANOLYSIS OF BENZOYL DERIVATIVES OF SUBSTITUTED PHENYLUREAS AND PHENYLTHIOUREAS
Kavalek, Jaromir,El Bahaie, Said,Sterba, Vojeslav
, p. 2103 - 2110 (2007/10/02)
The methanolysis rate constants and dissociation constants have been measured of benzoyl derivatives of substituted phenylureas and phenylthioureas.The dissociation constants of the thio derivatives are higher by 1 order of magnitude and the rate constants are higher by 2 orders of magnitude than the respective values of the oxygen analogues.Logarithms of the rate and dissociation constants have been correlated with Hammett ? constant; the ρ constant of the methanolysis of the oxygen derivatives is almost 2 * higher than that of the thio derivatives, which is explained by a change in the rate-limiting step.Methylation of the phenyl nitrogen atom increases the acidity by almost 2 orders of magnitude.This effect is due obviously to steric hindrance to the conjugation with the adjacent carbonyl or thiocarbonyl group.