Reactions of 2-(trifluoromethyl)-2-hydroxy-2H-chromenes with silyl enol ethers promoted by AlCl3

Abstract An efficient and straightforward nucleophilic substitution reaction between 2-(trifluoromethyl)-2-hydroxy-2 H -chromenes and various silyl enol ethers promoted by Lewis acid has been studied. A series of novel 4-functionalized-2-trifluoromethyl-3-ethoxycarbonyl-4 H -chromenes were prepared in good yields under mild conditions.