Ruthenium Catalyzed Selective Regio-and-Mono-Allylation of Cyclic 1,3-Diketones Using Allyl Alcohols as Substrates

ne new ruthenium-sulfonate catalyst Ru(Cp*)(eta(3)-C3H5) (p-CH3C6H4SO3)(2), (Cp* = pentamethylcyclopentadienyl), rapidly and regioselectively mono-allylates dimedone to the branched products using substituted allyl alcohols as substrates, without acid, base or other additives, under relatively mild conditions. We consider the ruthenium sulfonate to be a green alternative in that it uses allyl alcohols as substrate, (rather than carbonates, acetates, etc.) and therefore does not waste the leaving group. The catalyst induces rapid double allylation of various 1,3-diketones in high yield using allylic alcohol.