Janus Effect of Lewis Acid Enables One-Step Block Copolymerization of Ethylene Oxide and N-Sulfonyl Aziridine.
Angew Chem Int Ed Engl
; 62(18): e202300187, 2023 Apr 24.
Article
em En
| MEDLINE
| ID: mdl-36869751
ABSTRACT
One-step sequence-selective block copolymerization requires stringent catalytic control of monomers relative activity and enchainment order. It has been especially rare for An Bm -type block copolymers from simple binary monomer mixtures. Here, ethylene oxide (EO) and N-sulfonyl aziridine (Az) compose a valid pair provided with a bicomponent metal-free catalyst. Optimal Lewis acid/base ratio allows the two monomers to strictly block-copolymerize in a reverse order (EO-first) as compared with the conventional anionic route (Az-first). Livingness of the copolymerization facilitates one-pot synthesis of multiblock copolymers by addition of mixed monomers in batches. Calculation results reveal that a Janus effect of Lewis acid on the two monomers is key to enlarge the activity difference and reverse the enchainment order.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
China