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Temperature triggered alternating copolymerization of epoxides and lactones via pre-sequenced spiroorthoester intermediates.

ABSTRACT: We report the alternating copolymerization of caprolactone and epoxide through the in situ formation of pre-sequenced spiroorthoester monomer. The reaction is catalyzed by the temperature triggered, bifunctional cationic indium complex (±)-[(NN_iO_tBu)In(CH₂SiMe₃)][B(C₆F₅)₄] (1). 1 can catalyze the coupling of epoxide and lactone to form spiroorthoester at 60 °C and its double ring-opening polymerization at 110 °C to form poly(ether-alt-ester). The post-polymerization modification and degradation of the poly(ether-alt-ester) are further investigated.

SUBMITTER: Jung HJ

PROVIDER: S-EPMC8966630 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Temperature triggered alternating copolymerization of epoxides and lactones via pre-sequenced spiroorthoester intermediates.

Jung Hyuk-Joon HJ Goonesinghe Chatura C Mehrkhodavandi Parisa P

Chemical science 20220316 13

We report the alternating copolymerization of caprolactone and epoxide through the in situ formation of pre-sequenced spiroorthoester monomer. The reaction is catalyzed by the temperature triggered, bifunctional cationic indium complex (±)-[(NNiOtBu)In(CH2SiMe3)][B(C6F5)4] (1). 1 can catalyze the coupling of epoxide and lactone to form spiroorthoester at 60 °C and its double ring-opening polymerization at 110 °C ...[more]

PMID: 35432898

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