Synthesis of Chiral Sulfonyl Lactones via Copper‐Catalyzed Asymmetric Radical Reaction of DABCO⋅(SO2)

Abstract In the present work, an asymmetric copper‐catalyzed radical multi‐component cascade reaction of an unsaturated carboxylic acid, aryldiazonium tetrafluoroborate, and DABCO⋅(SO 2 ) 2 (DABSO) has been developed for the enantioselective synthesis of sulfonyl lactones. In this reaction, this SO 2 surrogate, DABSO was applied for the first time in the construction of chiral compounds. This multiple‐step asymmetric radical reaction was carried out under mild conditions and tolerated a wide range of substrates, resulting in the corresponding sulfonyl lactones with up to 95% chemical yields and 88% ee. The current reaction enriches the research contents of DABSO, and provides a new and efficient strategy to chiral functionalized lactones bearing quarternary stereogenic center. magnified image