Unsaturated acyclic alcohols of carbon numbers four and five reacted with boron trifluoride etherate to give eight ethers. Of these ethers, novel acyclic di-and tri-ethers were found in the reaction products of 2-methyl-2-propen-1-ol. Boron trifluoride etherate catalyzes double- bond migration, allylic rearrangement, intermolecular dehydration, and Markownikov addition reactions in unsaturated aliphatic alcohols.