Allylation of phenoxides by crown ethers and their polymers

Abstract

AbstractAllylation of sodium phenoxide in the presence of crown ethers produces a high ratio of O/O + C allylation when conducted in water, phenol, benzene, or diethyl ether. The striking increase in the product ratios is attributed to specific complexation of the crown ethers that facilitate the dissociation of the ion pair aggregate of the sodioderivative in benzene or diethyl ether. The crown ethers may act as a phase transfer catalyst when the reaction is run in water. Furthermore, the O/O + C ratios of the allylation strongly depend on the kind of crown ethers used. To examine their effect the allylation of sodium phenoxide was studied with various crown ethers, such as 18‐crown‐6, benzo‐18‐crown‐6, benzo‐15‐crown‐5, poly(vinylmonobenzo‐15‐crown‐5), and poly(vinylmono‐benzo‐18‐crown‐6), as catalysts. It was found that among these crown ethers poly(vinylmono‐benzo‐15‐crown‐5) was the most effective catalyst.