Radical Addition of SFCl to Cyclopropenes: Synthesis of (Pentafluorosulfanyl)cyclopropanes.

With the goal of accessing yet unknown SF-cyclopropyl building blocks, the radical addition of SFCl to cyclopropenes was investigated. Addition of the SF radical occurs regioselectively at the less substituted carbon of cyclopropenes and to the most hindered substituent at C3, while chlorine atom transfer proceeds with moderate to high levels of diastereocontrol. The carbon-chlorine bond in the resulting adducts can undergo subsequent radical reduction or be involved in a radical cyclization.