Nanocrystalline TiO2-HClO4:A novel,efficient and recyclable catalyst for the chemoselective N-Boc protection of amines under solvent-free conditions

Nanocrystalline TiO₂–HClO₄, as newly reported catalyst, has been used as an efficient and reusable catalyst for the chemoselective N-Boc protection of amines. The clean, mild acidity condition, quantitative yields of products, short reaction time and low reaction temperature are attractive features of this reaction. In practice, this method is a combination of a satisfactory synthesis and more significantly easy product isolation and purification.