Clean and fast oxidative transformation of thiols to disulfides under solvent-free conditions

We present here a fast, solvent-free synthesis of symmetrical disulfides using solid supported catalyst (Al₂O₃/KF). The reaction was performed at room temperature, by gentle heating or under MW irradiation. This efficient and improved method is general for liquid thiols, affording the disulfides in good to excellent yields. The catalytic system can be re-used two times without previous treatment and with comparable activity.