1-Propanephosphonic Acid Cyclic Anhydride (T3P) as an Efficient Promoter for the Lossen Rearrangement: Application to the Synthesis of Urea and Carbamate Derivatives
Basavalingappa Vasantha, Hosahalli P. Hemantha, Vommina V. Sureshbabu*
*Department of Chemistry, The University of South Dakota, Vermillion, SD 57069, USA, Email: sureshbabuvomminarediffmail.com
B. Vasantha, H. P. Hemantha, V. V. Sureshbabu, Synthesis, 2010, 2990-2996.
1-Propanephosphonic acid cyclic anhydride (T3P) promotes the synthesis of hydroxamic acids from carboxylic acids. Application of ultrasonication accelerates this conversion. Further, T3P has also been employed to activate the hydroxamates, leading to isocyanates via Lossen rearrangement. Trapping with suitable nucleophiles affords the corresponding ureas and carbamates.
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