Diels–Alder cycloadditions of 3,5-dibromo-2-pyrone with cycloalkenyl silyl ethers for the synthesis of bicarbocycles

3,5-Dibromo-2-pyrone underwent facile Diels–Alder [4+2] cycloadditions with cycloalkenyl silyl ethers to provide a series of tricyclolactones, with good to excellent chemical yields and stereoselectivity. The resulting cycloadducts could be readily converted into the corresponding bicarbocycles upon selective debromination and reductive lactone ring opening reactions.