233683-98-2Relevant academic research and scientific papers
Ring opening of N-hydroxyphthalimide to construct phenylurea derivatives
Wu, Yinhui,Lv, Bin,Zhang, Yanan,Gao, Pan,Zhang, Min,Yuan, Yu
, p. 2025 - 2033 (2021/05/29)
Arylurea and their analogues have been one of the most ubiquitous backbone during the past century, and extensive studies have been conducted to establish practical synthetic methods for their derivatives. In particular, it is an effective pathway to synthesize arylureas by using commercially available phthalimide compounds. Reported herein is a triethoxyphosphine promoted ring-opening of the N-hydroxyphthalimide (NHPI) by the nucleophilic attack of amines. This transformation shows a wide range of functional-group tolerance under mild reaction conditions.
One-Pot Reactions of N-(Mesyloxy)phthalimides with Secondary Amines to 2-Ureidobenzamides, 2-Ureidobenzoic Acids, Ethyl 2-Ureidobenzoates, or Isatoic Anhydrides
Guetschow, Michael
, p. 5109 - 5115 (2007/10/03)
The reaction of N-(mesyloxy)phthalimides with secondary amines was examined. Transformations are accomplished by one-pot reactions to optionally afford corresponding 2-ureidobenzamides, 2-ureidobenzoic acids, ethyl 2-ureidobenzoates, or isatoic anhydrides, respectively. The mechanism of the acid-catalyzed hydrolysis (or alcoholysis) of intermediate 2-ureidobenzamides to 2-ureidobenzoic acids (or esters) is discussed. A proton transfer mechanism involving the ureido moiety as an internal acid catalyst is proposed. Intermediate 2-ureidobenzoic acids undergo a further transformation to isatoic anhydrides. The utilization of the obtained 2-ureidobenzamides, 2-ureidobenzoic acids, and ethyl 2-ureidobenzoates to prepare 3,1-benzoxazin-4-ones is demonstrated.
