4-Cyanobenzenesulfonamides: Amine Synthesis and Protecting Strategy To Compliment the Nosyl Group.

4-Cyanobenzenesulfonamides of secondary amines were found to cleave to the parent amine cleanly under the action of thiol and base. This feature readily lends itself to the use of this motif as an amine protecting/activating group within a broader context of amine synthesis. The crystalline sulfonamides could be further elaborated by alkylation and arylation similarly to nitrobenzenesulfonamides. The sulfonamides could withstand conditions that functionalize nitroarenes, such as reductions and vicarious nucleophilic substitution reactions.