Copper-Catalyzed Carbonylative Synthesis of β-Homoprolines from N-Fluoro-sulfonamides

A new methodology for the carbonylative transformation of N-fluoro-sulfonamides into N-sulfonyl-beta-homoproline esters has been described. In the presence of a catalytic amount of Cu(OTf)(2), a range of beta-homoproline derivatives were prepared in moderate to good yield. The reaction proceeds via the intramolecular cyclization and intermolecular carbonylation of a free carbon radical. Notably, this procedure offers the possibility to build potential functionalized bioactive molecules.