Lewis Acid Catalyzed Carbon−Carbon Bond Cleavage of Aryl Oxiranyl Diketones: Synthesis of cis-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.羰基叶立德（Carbonyl ylide）是一类至关重要的反应中间体，可参与一系列1,3-偶极环加成反应。学界普遍认为，环氧乙烷的碳-碳键异裂是生成羰基叶立德最具原子经济性且最为简便直接的途径。然而在过往研究中，该类转化仅能在光化学与热化学条件下实现。本工作报道了一种室温合成策略：通过路易斯酸（Lewis acid）催化芳基环氧乙烷二酮的碳-碳键异裂得到羰基叶立德，随后使其与醛类发生[3+2]环加成反应，即可一步法非对映选择性合成顺式-2,5-二取代1,3-二氧戊环。