Regio‐ and Stereoselective Iodochlorination/Cross‐Coupling Strategy for Isomeric Trifluoromethylated Tetrasubstituted Alkenes

Trifluoromethylated tetrasubstituted alkenes are valuable motifs in biologically active compounds and functional materials, but their stereoselective synthesis remains challenging owing to the limited number of methods available. In this study, we describe a highly regio‐ and stereoselective iodochlorination of trifluoromethylated internal alkynes using N ‐iodosuccinimide and lithium chloride in an acetic acid/tetrahydrofuran mixed solvent system. The resulting vicinal dihalides serve as versatile intermediates for sequential cross‐coupling reactions, thereby providing efficient and stereodefined routes to densely substituted alkenes. Importantly, judicious choice of both substrates and coupling partners enables the selective preparation of distinct alkene isomers, demonstrating the method's flexibility. This approach offers a straightforward and general strategy for constructing complex trifluoromethylated alkenes, with potential applications in medicinal chemistry, agrochemicals, and materials science, where precise control of alkene geometry is essential.