Abstract
Ionic pair tetrabutylammonium halide (TBAX) was efficient initiator in anionic ring-opening polymerizations (AROPs) of N-sulfonyl aziridines, in which the tetrabutylammonium fluoride (TBAF) was the optimal initiator effect controlled/living AROPs. TBAX initiated AROPs of 2-methyl-N-tosylaziridine (TsMAz) by relative activities on halide X in sequence of F > Cl > Br > I, which was corroborated to the nucleophilicities of the halides. Homopolymers and diblock copolymers of TsMAz and EsMAz were prepared. The AROPs possessed living nature by first order kinetics with fast polymerizations (0.5 to several hours), high conversions (90–99%), narrow dispersities (Đ < 1.16), and predicted molecular weights. Mechanism of initiation by direct attack on the aziridine ring with fluoride and propagation by sulfonyl amidate anion was proposed. This protocol provided new entry in design of catalyst/initiator of ionic pair for polymerizations, and developed synthetic toolbox for mild and efficient anionic ring-opening polymerizations.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.