Use of Selenium-Bound Resin for the Solid-Phase Synthesis of Substituted Isoxazolyl-Substituted (E)-Olefins

[reaction: see text] The preparation of isoxazolyl- and isoxazolinyl-substituted olefins, based on polystyrene-supported selenenyl bromide, is described. Key steps include 1,3-dipolar cycloadditions and the alpha-alkylation reaction of selenium resins. The polystyrene-supported selenium resins used here not only facilitate separation of products, but also assist the crucial reaction of alpha-alkylation and selenoxide syn-elimination, which ensures the purity of the products.