Transition‐Metal‐Free Visible‐Light‐Induced Alkynylation of Silacarboxylic Acids

Abstract An operationally simple and mild protocol for the visible‐light‐induced intermolecular coupling of silacarboxylic acids with sulfonyl alkynes to form alkynylsilanes is presented. This study highlights the use of inexpensive and readily available 4CzIPN as a photocatalyst, along with more stable silacarboxylic acids as silyl radical precursors, enabling the synthesis of a variety of alkynylsilanes in good to excellent yields, notably without the need for transition metals. The transformation offers several key advantages, including a broad substrate scope, good functional group tolerance, and compatibility with heterocyclic substrates. Furthermore, both the scale‐up reaction and the late‐stage functionalization of natural products have been successfully achieved under mild conditions. These features make the process not only efficient but also versatile and suitable for a wide range of applications in chemical synthesis and modification.