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Polyphosphinoborane Block Copolymer Synthesis Using Catalytic Reversible Chain-Transfer Dehydropolymerization.

ABSTRACT: An amphiphilic block copolymer of polyphosphinoborane has been prepared by a mechanism-led strategy of the sequential catalytic dehydropolymerization of precursor monomers, H₃ B ⋅ PRH₂ (R=Ph, n-hexyl), using the simple pre-catalyst [Rh(Ph₂ PCH₂ CH₂ PPh₂ )₂ ]Cl. Speciation, mechanism and polymer chain growth studies support a step-growth process where reversible chain transfer occurs, i.e. H₃ B ⋅ PRH₂ /oligomer/polymer can all coordinate with, and be activated by, the catalyst. Block copolymer [H₂ BPPhH]₁₁₀ -b-[H₂ BP(n-hexyl)H]₁₁ can be synthesized and self-assembles in solution to form either rod-like micelles or vesicles depending on solvent polarity.

SUBMITTER: Race JJ

PROVIDER: S-EPMC10107156 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Polyphosphinoborane Block Copolymer Synthesis Using Catalytic Reversible Chain-Transfer Dehydropolymerization.

Race James J JJ Heyam Alex A Wiebe Matthew A MA Diego-Garcia Hernandez J J Ellis Charlotte E CE Lei Shixing S Manners Ian I Weller Andrew S AS

Angewandte Chemie (International ed. in English) 20221208 3

An amphiphilic block copolymer of polyphosphinoborane has been prepared by a mechanism-led strategy of the sequential catalytic dehydropolymerization of precursor monomers, H3 B ⋅ PRH2 (R=Ph, n-hexyl), using the simple pre-catalyst [Rh(Ph2 PCH2 CH2 PPh2 )2 ]Cl. Speciation, mechanism and polymer chain growth studies support a step-growth process where reversible chain transfer occurs, i.e. H3 B ⋅ PRH2</su ...[more]

PMID: 36394131

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