Wei Wu, Tobias M. Milzarek, Matthew D. Wodrich, Jerome Waser
Cyclopropenes are the smallest unsaturated carbocycles. They possess exceptionally high ring strain, resulting in unique reactivity, enabling C═C bond functionalization and ring-opening transformations. Herein, we report a copper-mediated trifluoromethylation of cyclopropenyl benziodoxole (CpBX) reagents, providing access to previously inaccessible, yet highly useful, sp 2 -trifluoromethylated cyclopropenes. Subsequent functionalizations of these novel strained ring building blocks enable access to highly substituted trifluoromethylated cyclopropanes, difluoromethylene cyclopropanes and noncyclic trifluoromethylated compounds.