Controlled ring‐opening polymerization of lactide by bis‐sulfonamide/amine associations: Cooperative hydrogen‐bonding catalysis

The bis‐sulfonamide m ‐C 6 H 4 (SO 2 NHPh) 2 efficiently promotes the ring‐opening polymerization of lactide when combined with tertiary amines, such as N , N ‐dimethylaminopyridine. Polylactides of controlled molecular weights ( M n up to 17,700 g mol −1 ) and very narrow molecular weight distributions ( M w / M n < 1.11) are obtained under mild conditions and in a living fashion. The reaction takes place through a bifunctional mechanism involving activation of both the alcohol and the monomer. Modulation of the sulfonamide component supports cooperative dual hydrogen‐bonding of lactide involving the two (SO 2 NHAr) moieties.