Radical Silyldifluoromethylation of Electron-Deficient Alkenes.

A reaction of bromo- and iododifluoromethyl-substituted silanes with electron-deficient alkenes in the presence of an N-heterocyclic carbene borane complex is described. The reaction is performed under irradiation with light-emitting diodes and proceeds via a radical chain mechanism. The resulting products, the functionalized silicon reagents, can undergo chemoselective transformations involving either the silyldifluoromethyl fragment or the functional group.