The 1, 4-elimination reaction of 1-allyloxy-4-methoxy-(2Z)-alkenes with n-butyllithium is shown to proceed in a marked preference to the [2, 3] Wittig rearrangement to afford the allylic (1Z, 3E)-dienyl ethers in high stereoselectivities. The synthetic utility of this method is demonstrated by the Claisen rearrangement of the dienyl ethers thus obtained.
