Gold-catalyzed domino cyclization and oxidative coupling reaction for synthesis of dicoumarins was studied. Gold was thought to be an unreactive metal before its catalyzed reaction was discovered. HAuCl4 was suspended in dry 1,2-dichloroethane (DCE), whereas protic solvent gave only monomer and UV absorption and fluorescence properties of dicoumarins were similar to those of monomers. The crude product was purified by flash column chromatography on silica and gold catalyst performed two different functions. Dicoumarins, scaffolds of natural products has interesting biological properties whereas, potential photostable UV-absorbent materials were accessed in two steps from commercially available starting materials. The reaction generally proceeded in moderate-to-good yields, tolerating a variety of substituents on the aromatic moiety.
