N-Acylbenzotriazoles as Proficient Substrates for an Easy Access to Ureas, Acylureas, Carbamates, and Thiocarbamates via Curtius Rearrangement Using Diphenylphosphoryl Azide (DPPA) as Azide Donor

Abstract A diverse range of ureas, N-acylureas, carbamates, and thiocarbamates has been synthesized in good to excellent yields by reacting N-acylbenzotriazoles individually with amines or amides phenols thiols the presence diphenylphosphoryl azide (DPPA) as a suitable donor anhydrous toluene at 110 °C for 3–4 hours. In this route, DPPA was found be alternative trimethylsilyl sodium Curtius degradation. The high reaction yields, one-pot metal-free conditions, straightforward nature, easy handling, use readily available reagents, many cases avoidance column chromatography are notable features devised protocol.