Ring-Cleavage Reactions of Five- and Six-Membered Cyclic Ethers with Organolithium Compounds

In the presence of one equivalent of boron trifluoride etherate, organolithium compounds cause the ring cleavage reactions of tetrahydrofurans and tetrahydropyran to give the corresponding long-chain alcohols in moderate yields. These reactions are highly regioselective for unsymmetric cyclic ethers.