Lewis Acid Catalyzed Carbon−Carbon Bond Cleavage of Aryl Oxiranyl Diketones: Synthesis of <i>cis</i>-2,5-Disubstituted 1,3-Dioxolanes

Carbonyl ylide is one of the most important intermediates which can undergo a series of 1,3-dipolar cycloaddition reactions. The C−C heterolysis of oxirane is believed to be the most atom-economic and straightforward way to generate carbonyl ylide. However, this chemistry was only achieved under photochemical and thermal conditions in past years. In this work, the one-step diastereoselective synthesis of cis-2,5-disubstituted 1,3-dioxolanes via [3 + 2] cycloadditions of aldehydes and carbonyl ylide, which is obtained from Lewis acid catalyzed C−C bond heterolysis of aryl oxiranyl diketones at ambient temperature, is described.