Proton transfer anionic polymerization with C-H bond as the dormant species

Nat Chem. 2024 Oct;16(10):1630-1637. doi: 10.1038/s41557-024-01572-3. Epub 2024 Jul 4.

Abstract

Living anionic polymerization-the most common living polymerization and the one with the longest history-generally requires stringent, water-free conditions and one metal initiator per polymer chain. Here we present the proton transfer anionic polymerization of methacrylates using acidic C-H bonds as the dormant species that are activated by base catalysts. The polymerization mechanism involves reversible chain transfer or termination of the growing enolate species. A weakly acidic compound, such as an alkyl isobutyrate, serves as the initiator or chain-transfer agent in the presence of a bulky potassium base catalyst to produce a polymer chain and, thereby, diminishes the metal compound per chain ratio. An added alcohol serves as a reversible terminator to tame the propagation. End-functionalized, star, block and graft polymers are easily accessible from compounds with C-H bonds.