Transition metal-free regioselective access to 9,10-dihydroanthracenes via the reaction of anthracenes with elemental phosphorus in the KOH/DMSO system

Abstract Anthracene and its 9- or 9,10-substituted (Me, Ph, Cl, Br) derivatives react with red phosphorus (P n ) in the KOH/DMSO superbase system at 85–120 °C to afford 9,10-dihydroanthracenes in good to excellent yields, thus providing simple and clean access to these extensively used dihydroaromatics.