1,2-ELIMINATION OF ALCOHOL FROM HOMOALLYL ETHERS UNDER THE INFLUENCE OF MIXED METAL BASES

Article abstract of DOI:10.1016/S0040-4020(01)82022-6

Lithium diisopropylamide in the presence of catalytic amounts of potassium tert-butoxide smoothly converts homoallyl or homobenzyl type ethers to dienes (e.g., 1, 3, 5, 26) or styrenes (2). γ,δ-Unsaturated acetals give 1,3-dienyl ethers (e.g., 4) and 4-alkylidenetetrahydropyrans or dihydropyrans produce a variety of dienols (e.g., 6 - 17, 20 - 22). - If there is a choice, the new double bond is formed with high trans-selectivity while the configuration of existing double bonds is retained. - The elimination mode is syn-periplanar and concerted, though E1cb like.