Tailoring the Reactivity of the Langlois Reagent and Styrenes with Cyanoarenes Organophotocatalysts under Visible-Light.

The unprecedented selective and straightforward one-step access to fluoroalkylated hexestrol derivatives, nonsteroidal estrogens, is achieved in good to excellent isolated yields under organophotoredox conditions by using the stable and easy to handle Langlois reagent. Furthermore, the challenging selective hydrotrifluoromethylation of styrenes proceeds under mild reaction conditions without the requirement of any additive. We assume that the solvent drives the reaction pathway towards either the reduction or the dimerization of the radical intermediate generated after initial addition of the fluoroalkyl radical to the styrene. The versatility of the developed system is also extended to encompass radical-radical cross-coupling as exemplified here using cyanopyridine. Mechanistic investigations including luminescence and EPR spectroscopy allow to shed the light on the different mechanisms.