Stereoselective Synthesis of (Z)-α-Alkylidene-γ-Butyrolactones via Pd-Catalyzed CO Insertion and Cyclization

摘要

Four new (Z)-2-phenoxymethylene-4-pentanolide derivatives and four (Z)-2-phenoxymethyl-2-penten-γ-lactone derivatives were prepared via Pd-catalyzed carbon monoxide insertion and intramolecular cyclization. All compounds were characterized by IR, ~1H NMR, ~(13)C NMR, MS spectra and elemental analysis. The plausible mechanism of the reaction was discussed.