A green synthesis of isatoic anhydrides from isatins with urea-hydrogen peroxide complex and ultrasound.
The oxidation of isatins at room temperature, using the cheap and environmentally friendly urea-hydrogen peroxide complex and ultrasonic irradiation, has been investigated. The ultrasonic irradiation dramatically reduces the reaction time. With easy and reproducible reaction procedures, different isatoic anhydrides were obtained in excellent yield and with high purity.
Deligeorgiev
Todor
T
University of Sofia, Faculty of Chemistry, 1164 Sofia, Bulgaria. Electronic address: ohttgd@chem.uni-sofia.bg.
Vasilev
Aleksey
A
University of Sofia, Faculty of Chemistry, 1164 Sofia, Bulgaria.
Vaquero
Juan J
JJ
University of Alcalá, Faculty of Pharmacy, 28871 Alcalá de Henares, Madrid, Spain.
Alvarez-Builla
Julio
J
University of Alcalá, Faculty of Pharmacy, 28871 Alcalá de Henares, Madrid, Spain.