A method for producing 3-methyl-2-pentene which is substantially free of any other C.sub.6 olefin, except 2-ethyl-1-butene, by first producing a stream that contains 2-ethyl-1-butene from the trimerization of ethylene, and second by recovering the 2-ethyl-1-butene as 3-methyl-2-pentene via etherification, separation of the ether, and decomposition of the ether back to predominantly 3-methyl-2-pentene with some 2-ethyl-1-butene.