Gold(III) chloride (HAuCl4·3H2O) in PEG: A new and efficient catalytic system for the synthesis of functionalized spirochromenes Original Research Article

Gold(III) chloride (HAuCl4·3H2O) in PEG 400 was found to be an efficient catalytic system for the synthesis of biologically important functionalized spirochromene derivatives via one-pot three-component reaction of isatins/acenaphthoquinone, active methylene compounds and cyclic 1,3-diketones/4-hydroxycoumarin. A new catalytic system, recyclability of reaction medium, little reaction times and excellent yields with easy workup render this protocol more attractive and economically viable.