Total Synthesis of Allolaurinterol

The total synthesis of allolaurinterol was accomplished. The cyclopentanone ring was formed via Sc(OTf)3-catalyzed intramolecular cyclization of β-keto esters as the key reaction, which was developed based on the 1,3-rearrangement of cyclic enol ethers. While methylation at the C(2′) position afforded a stereoisomeric mixture, the undesired epimer at C(2′) was recycled through epimerization via thermodynamic enolate formation followed by a kinetic protonation, thereby improving synthetic efficiency. Consequently, allolaurinterol was obtained from m-cresol in 11 steps with an overall yield of 7%.