Olefins are widely available at low costs, which explains
the usefulness
of developing new methods for their functionalization. Here we report
a simple protocol that uses a photoredox catalyst and an inexpensive
thiol catalyst to stitch together two olefins, forming a new C–C
bond. Specifically, an electron-poor olefin is reduced by the photoredox
catalyst to generate, upon protonation, a carbon radical, which is
then captured by a neutral olefin. This intermolecular cross-coupling
process provides a tool for rapidly synthesizing sp3-dense
molecules from olefins using an unconventional disconnection.