Treatment of methyl 3-hydroxy-8-oxabicyclo[3.2.1]oct-2-ene-2-carboxylate (I) with N-phenyl trifluoromethanesulfonimide leads to the vinyl triflate (II). Suzuki coupling of triflate (II) with 3,4-dichlorophenylboronic acid (III) furnishes the oxabicyclooctene adduct (IV), which is further reduced to the oxabicyclooctane (V) with SmI2. Ester reduction in (V) with LiAlH4 provides alcohol (VI). This is finally esterified with 4-pentenoyl chloride (VII) to furnish the title compound.