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The Detection and Reactivity of Silanols and Silanes Using Hyperpolarized ²⁹ Si Nuclear Magnetic Resonance.

ABSTRACT: Silanols and silanes are key precursors and intermediates for the synthesis of silicon-based materials. While their characterization and quantification by ²⁹ Si NMR spectroscopy has received significant attention, it is a technique that is limited by the low natural abundance of ²⁹ Si and its low sensitivity. Here, we describe a method using p-H₂ to hyperpolarize ²⁹ Si. The observed signal enhancements, approaching 3000-fold at 11.7?T, would take many days of measurement for comparable results under Boltzmann conditions. The resulting signals were exploited to monitor the rapid reaction of tris(tert-butoxy)silanol with triflic anhydride in a T₁ -corrected process that allows for rapid quantification. These results demonstrate a novel route to quantify dynamic processes and intermediates in the synthesis of silicon materials.

SUBMITTER: Rayner PJ

PROVIDER: S-EPMC7027454 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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The Detection and Reactivity of Silanols and Silanes Using Hyperpolarized 29 Si Nuclear Magnetic Resonance.

Rayner Peter J PJ Richardson Peter M PM Duckett Simon B SB

Angewandte Chemie (International ed. in English) 20200109 7

Silanols and silanes are key precursors and intermediates for the synthesis of silicon-based materials. While their characterization and quantification by 29 Si NMR spectroscopy has received significant attention, it is a technique that is limited by the low natural abundance of 29 Si and its low sensitivity. Here, we describe a method using p-H2 to hyperpolarize 29 Si. The observed signal enhancements, approaching 3000-fold at 11.7 T, would take many ...[more]

PMID: 31833623

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