Sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 nanocrystallites as a magnetically Brønsted acid for N-formylation of amines Original Research Article

Treatment of aqueous formic acid (85%) with structurally diverse amines in the presence of a catalytic amount of sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 [HAp@-γ-Fe2O3] (0.9 mol.%) as a heterogeneous, reusable and highly efficient catalyst gave the corresponding formamides in good to excellent yields at room temperature. The magnetically catalytic system was recovered by-passing time consuming filtration operation by using an external magnet device. In addition to facility, this methodology, it also enhances product purity and promises economic as well as environmental benefits.