Synthesis of α-SF5 Ketones by Oxypentafluorosulfanylation of Alkynes with SF5Cl and Oxygen.

Herein for the first time, we disclose a practical and straightforward approach to access α-SF5 ketones via direct oxypentafluorosulfanylation of alkynes with SF5Cl and oxygen under acidic conditions by one step. The protocol features mild reaction conditions, broad substrate scope, good functional group compatibility and can be applied to late-state functionalization of complex natural products and pharmaceuticals. A radical mechanism involving SF5 radical addition to triple bonds followed by O2 capture is proposed.