According to the mechanism involving palladium enolate intermediates in divalent palladium catalyzed nucleophile-alkyne-α，β-unsaturated carbonyl tandem additions, the reactions of the enyne ester 1 with electrophiles under the catalysis of divalent palladium were examined. Employing acetyl chloride as the electrophile afforded the β-acetoxyvingly-γ-butyrolactone 3 as the product, which provided an experimental evidence to the mechanism involving the palladium enolate intermediate.
