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Calix[4]pyrrolato Aluminate Catalyzes the Dehydrocoupling of Phenylphosphine Borane to High Molar Weight Polymers.

ABSTRACT: High molar weight polyphosphinoboranes represent materials with auspicious properties, but their preparation requires transition metal-based catalysts. Here, calix[4]pyrrolato aluminate is shown to induce the dehydropolymerization of phosphine boranes to high molar mass polyphosphinoboranes (up to M_n =43 000 Da). Combined GPC and ³¹ P DOSY NMR spectroscopic analyses, quantum chemical computations, and stoichiometric reactions disclose a P-H bond activation by the cooperative action of the square-planar aluminate and the electron-rich ligand framework. This first transition metal-free catalyst for P-B dehydrocoupling overcomes the problem of residual d-block metal impurities in the resulting polymers that might interfere with the reproducibility of the properties for this emerging class of inorganic materials.

SUBMITTER: Schon F

PROVIDER: S-EPMC9313825 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Calix[4]pyrrolato Aluminate Catalyzes the Dehydrocoupling of Phenylphosphine Borane to High Molar Weight Polymers.

Schön Florian F Sigmund Lukas M LM Schneider Friederike F Hartmann Deborah D Wiebe Matthew A MA Manners Ian I Greb Lutz L

Angewandte Chemie (International ed. in English) 20220329 22

High molar weight polyphosphinoboranes represent materials with auspicious properties, but their preparation requires transition metal-based catalysts. Here, calix[4]pyrrolato aluminate is shown to induce the dehydropolymerization of phosphine boranes to high molar mass polyphosphinoboranes (up to M<sub>n</sub> =43 000 Da). Combined GPC and <sup>31</sup> P DOSY NMR spectroscopic analyses, quantum chemical computations, and stoichiometric reactions disclose a P-H bond activation by the cooperativ ...[more]

PMID: 35235698

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