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A Supported Ziegler-Type Organohafnium Site Metabolizes Polypropylene

[Image: see text] Cp(2)Hf(CH(3))(2) reacts with silica containing strong aluminum Lewis sites to form Cp(2)Hf–(13)CH(3)(+) paired with aluminate anions. Solid-state NMR studies show that this reaction also forms neutral organohafnium and hafnium sites lacking methyl groups. Cp(2)Hf–(13)CH(3)(+) reac...

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Detalles Bibliográficos
Autores principales: Samudrala, Kavyasripriya K., Conley, Matthew P.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2023
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10655186/
https://www.ncbi.nlm.nih.gov/pubmed/37921588
http://dx.doi.org/10.1021/jacs.3c05940
Descripción
Sumario:[Image: see text] Cp(2)Hf(CH(3))(2) reacts with silica containing strong aluminum Lewis sites to form Cp(2)Hf–(13)CH(3)(+) paired with aluminate anions. Solid-state NMR studies show that this reaction also forms neutral organohafnium and hafnium sites lacking methyl groups. Cp(2)Hf–(13)CH(3)(+) reacts with isotatic polypropylene (iPP, M(n) = 13.3 kDa; Đ = 2.4; mmmm = 94%; ∼110 C(3)H(6)/Hf) and H(2) to form oils with moderate molecular weights (M(n) = 290–1200 Da) in good yields. The aliphatic oils show characteristic (13)C{(1)H} NMR properties consistent with complete loss of diastereoselectivity and formation of regioirregular errors under 1 atm H(2). These results show that a Ziegler–Natta-type active site is compatible in a common reaction used to digest waste plastic into smaller aliphatic fragments.