Prins–Arylthiolation Reaction on Terpenoids: Diastereoselective Synthesis of 4‐Arylthiooctahydro‐2H‐chromenes

Abstract (–)‐Isopulegol undergoes Prins‐arylthiolation with different aldehydes and cyclohexanone in the presence of HBF 4 · OEt 2 to generate a library of 4‐arylthiooctahydro‐2 H ‐chromene derivatives in good to excellent yields with moderate to high cis selectivity at ambient temperature in dichloromethane. Readily available HBF 4 · OEt 2 as a catalyst outshines CF 3 CO 2 H, which is generally used in excess amounts in Prins cyclization and domino Prins‐arylthiolation reactions.