A Cation-Dependent Dual Activation Motif for Anionic Ring-Opening Polymerization of Cyclic Esters.
Journal of the American Chemical Society
A new organocatalyst for the ring-opening polymerization of lactones has been identified. Under the tested conditions, the anions of 2,2'-bisindole promote fast, living polymerizations (as short as 10 ms) which are selective for chain elongation over transesterification (D ≤ 1.1). While structurally related to (thio)urea anion catalysts, anions of 2,2'-bisindole activate the monomer via the counterion rather than through hydrogen bonding. This new activation motif enables modulation of the polymerization rate by 2 orders of magnitude by changing the counterion.
View details for DOI 10.1021/jacs.2c01436
View details for PubMedID 35504294
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