Synthesis of Biscoumarin and 3,4-Dihydropyrano[c]chromene Derivatives Catalysed by Sodium Dodecyl Sulfate (SDS) in Neat Water

A simple and efficient one-pot synthesis of biscoumarin and 3,4-dihydropyrano[c] chromene derivatives using catalytic amounts of SDS in water medium is reported. The catalyst can be recovered by simple filtration and reused.