Synthesis of aryl tri- and difluoromethyl thioethers via a C-H-thiocyanation/fluoroalkylation cascade.
An AlCl3 -catalyzed CH thiocyanation was discovered and combined with a Langlois-type trifluoromethylation to afford aryl trifluoromethyl thioethers directly from arenes, N-thiocyanatosuccinimide (NTS) and Ruppert-Prakash reagent. An analogous combination with a copper-mediated difluoromethylation gives access to aryl difluoromethyl thioethers. Both processes proceed with exceptional regioselectivity for the most electron-rich, sterically least hindered position of the arene. The sulfur and fluoroalkyl groups originate from different sources, so that the use of expensive, preformed fluoroalkylthiolation reagents is avoided.
FB Chemie-Organische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse Geb. 54, 67663 Kaiserslautern (Germany) http://www.chemie.uni-kl.de/goossen.
Kévin
K
Jouvin
FB Chemie-Organische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse Geb. 54, 67663 Kaiserslautern (Germany) http://www.chemie.uni-kl.de/goossen.
Christian
C
Matheis
FB Chemie-Organische Chemie, Technische Universität Kaiserslautern, Erwin-Schrödinger-Strasse Geb. 54, 67663 Kaiserslautern (Germany) http://www.chemie.uni-kl.de/goossen. goossen@chemie.uni-kl.de.
Lukas J
LJ
Goossen
electrophilic substitution; fluorine; fluoroalkylthiolation; sulfur; synthetic methods