Metal-Free Ring-Opening Metathesis Polymerization with Hydrazonium Initiators.
Phong K QuachJesse H HsuIvan KeresztesBrett P ForsTristan H LambertPublished in: Angewandte Chemie (International ed. in English) (2022)
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.
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