A simple, rapid, and efficient protocol for the chemoselective N-Boc protection of amines using sulfamic acid as catalyst is described. N-Boc protection of various structurally diverse aliphatic, aromatic, alicyclic, and heterocyclic amines (1°, 2°, 3°) was carried out with (Boc) 2O using sulfamic acid as catalyst (5mol%) at room temperature under solventless conditions. The advantages of this method are simplicity, shorter reaction times (1–15min), ...