Visible‐Light‐Driven Photoredox [2 + 1] Cycloaddition of Sulfoxonium Ylides With Alkenes

ABSTRACT Cyclopropane motifs are widely found in pharmaceuticals, natural products, and functional materials; however, current synthetic methods are often limited by harsh conditions and the requirement for precious metal catalysts. Herein, we have developed a visible‑light‑driven photoredox [2 + 1] cycloaddition strategy, which generates reactive carbon‑centered radicals via single‑electron oxidation of sulfoxonium ylides, followed by an S N 2 process to achieve cyclopropanation of alkenes. This method requires neither metal catalysts nor additives, and features mild conditions, good substrate compatibility for activated alkenes and various sulfoxonium ylides, and operational simplicity, offering a complementary approach to traditional methods and paving a new way for green cyclopropane synthesis.