Amination via Smiles Rearrangement

The Bucherer reaction is a well known method for the synthesis of amines from phenols using the reagent combination of NaHSO₃ and NH₃. 2-Bromoisobutyramide (1) is an effective alternate reagent for the synthesis of aromatic amines from phenols, via a one pot Smiles rearrangement²⁾ under mild conditions. For example, phenol 2 was reacted with 1 under alkali conditions to give phenoxyether derivative 3. Then NaOH was added, and the mixture was heated to provide the rearrangement product 4. This product was hydrolyzed to give aniline derivative 5 in a 63% overall yield.^1a) The obtained aniline derivatives are useful starting materials for medicines, functional materials, etc. In addition, the present one pot reaction sequence can be applied to thiophenols.^1b)