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Metal-Free Ring-Opening Metathesis Polymerization with Hydrazonium Initiators.

ABSTRACT: The ring-opening metathesis polymerization (ROMP) of cyclopropenes using hydrazonium initiators is described. The initiators, which are formed by the condensation of 2,3-diazabicyclo[2.2.2]octane and an aldehyde, polymerize cyclopropene monomers by a sequence of [3+2] cycloaddition and cycloreversion reactions. This process generates short chain polyolefins (M_n ≤9.4 kg mol^-1 ) with relatively low dispersities (Đ≤1.4). The optimized conditions showed efficiency comparable to that achieved with Grubbs' 2^nd generation catalyst for the polymerization of 3-methyl-3-phenylcyclopropene. A positive correlation between monomer to initiator ratio and degree of polymerization was revealed through NMR spectroscopy.

SUBMITTER: Quach PK

PROVIDER: S-EPMC9149102 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Metal-Free Ring-Opening Metathesis Polymerization with Hydrazonium Initiators.

Quach Phong K PK Hsu Jesse H JH Keresztes Ivan I Fors Brett P BP Lambert Tristan H TH

Angewandte Chemie (International ed. in English) 20220413 24

The ring-opening metathesis polymerization (ROMP) of cyclopropenes using hydrazonium initiators is described. The initiators, which are formed by the condensation of 2,3-diazabicyclo[2.2.2]octane and an aldehyde, polymerize cyclopropene monomers by a sequence of [3+2] cycloaddition and cycloreversion reactions. This process generates short chain polyolefins (Mn ≤9.4 kg mol-1 ) with relatively low dispersities (Đ≤1.4). The optimized conditions showed efficiency comparable to ...[more]

PMID: 35302707

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