Curtius Rearrangement of Aromatic Carboxylic Acids to Access Protected Anilines and Aromatic Ureas
Hélène Lebel* and Olivier Leogane
*Département de chimie, Université de Montréal, P.O. Box 6128, Station Downtown, Montréal, Québec, Canada, H3C 3J7, Email: helene.lebelumontreal.ca
H. Lebel, O. Leogane, Org. Lett., 2006, 8, 5717-5720.
DOI: 10.1021/ol0622920
Abstract
The reaction of di-tert-butyl dicarbonate or a chloroformate and sodium azide with an aromatic carboxylic acid produces the corresponding acyl azide. The acyl azide undergoes a Curtius rearrangement to form an isocyanate derivative which is trapped either by an alkoxide or by an amine to form the aromatic carbamate or urea.
see article for more examples
Boc-Protected Amines via a Mild and Efficient One-Pot Curtius Rearrangement
H. Lebel, O. Leogane, Org. Lett., 2005, 7, 4107-4110.
Key Words
Curtius Rearrangement, aryl amines, anilines, carbamates, tert-butyl carbamates, ureas
ID: J54-Y2006-3890