Synthesis of sulfonated naphthols via metal-free oxidative coupling of beta-tetralone and sodium sulfinates

The efficient synthesis of sulfonated naphthols was realized by dehydroaromatization of β-tetralones with sodium sulfinates under metal-free conditions. Iodine-containing reagents played an important role in this oxidative coupling process. Sodium sulfinates serve as a stable and readily available sulfur source, providing sulfones in good to excellent yields. A wide range of functional groups were well tolerated in this reaction.