Access to N-cyanosulfoximines by transition metal-free iminations of sulfoxides

A transition metal-free synthesis of N-cyanosulfoximines from sulfoxides using N-chlorosuccinimide (NCS) as oxidising agent and cyanamide as nucleophilic amine source is reported. The products are obtained in moderate to excellent yields. The protocol enables an easy access to N-cyanosulfoximines from readily available starting materials under inversion of configuration at a preexisting stereogenic center.