Total Synthesis of (±)‐Pentalenolactone A Methyl Ester

Abstract

Ringing it up: The methyl ester of pentalenolactone A has been obtained through the stereoselective synthesis of a cyclopentenone by a combination of the Co-mediated Pauson–Khand reaction (PKR) of enyne 1, and the construction of a quaternary-carbon-based strained α-methylidene-δ-pentyrolactone core through a trimethylsilyl (TMS) mediated, telescoped intramolecular Michael olefination (TIMO) reaction of keto-phosphonate 2.