Reusable Bronsted Acidic Ionic Liquid Efficiently Catalyzed N-Formylation and N-Acylation of Amines

We disclose efficient and green N-formylation and N-acylation methodologies of various amines with carboxylic acids for the synthesis of versatile amides in the presence of Bronsted acidic ionic liquid. Furthermore, the N-formylation and N-acylation with DMF and DMA have also been achieved in the same catalytic system. Notably, the catalyst in this catalytic solvent-free protocol could be easily recycled for up to five consecutive cycles with slight loss of activity.