Silver-Mediated Radical Cyclization of Alkynoates and α‑Keto Acids Leading to Coumarins via Cascade Double C–C Bond Formation

A novel
and convenient silver-mediated radical cyclization method
for the synthesis of coumarin derivatives via the direct difunctionalization
of alkynoates with α-keto acids through double C–C bond
formation under mild conditions has been developed. This new method
is highly efficient and practical, and the starting materials are
readily prepared. The present method should provide a useful strategy
for the construction of coumarin motifs.

本研究开发了一种新颖便捷的银介导自由基环化（radical cyclization）方法，可在温和条件下，通过炔酸酯（alkynoates）与α-酮酸（α-keto acids）的直接双官能团化反应，经双重C-C键形成过程合成香豆素衍生物（coumarin derivatives）。该方法高效实用，且起始原料易于制备，可为香豆素骨架的构建提供一条实用策略。