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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

Mangal S. Yadav, Sumt K. Singh, Anand K. Agrahari, Anoop S. Singh, Vinod K. Tiwari

*Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi, 221005, India, Email:

M. S. Yadav, S. K. Singh, A. K. Agrahari, A. S. Singh, V. K. Tiwari, Synthesis, 2021, 53, 2494-2502.

DOI: 10.1055/a-1399-3823 (free Supporting Information)

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The reaction of N-acylbenzotriazoles with diphenylphosphoryl azide (DPPA) as a suitable azide donor followed by amines or amides or phenols or thiols in anhydrous toluene at 110C for 3-4 hours provides a diverse range of ureas, N-acylureas, carbamates, and thiocarbamates in very good yields. DPPA was found to be a good alternative to trimethylsilyl azide and sodium azide for the Curtius degradation.

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Key Words

N-acylbenzotriazoles, N-acylureas, benzotriazoles, Curtius rearrangement, diphenylphosphoryl azide, carbamates, thiocarbamates, ureas

ID: J66-Y2021