Rhenium-catalyzed α-alkylation of enol acetates with α-alkyl-substituted β-diketones

When enol acetates were treated with α-alkyl-substituted β-diketones in the presence of a catalytic amount of a rhenium complex, such as ReBr(CO)5, the carbon–carbon bond formation proceeded by the elimination of β-dicarbonyl units of α-alkyl-substituted β-diketones to give the corresponding α-alkylated carbonyl compounds in moderate to good yields.