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Updated: May 27, 2026

Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Hydrosilylation of alkynes by Ni(CO)3-stabilized silicon(II) hydride
Miriam Stoelzel1, Carsten Präsang, Shigeyoshi Inoue
1Technische Universität Berlin, Institut für Chemie: Metalorganics and Inorganic Materials, Sekr. C2, Strasse des 17. Juni 135, 10623 Berlin, Germany.
Abstract:
Not copy and paste: Although β-diketiminato ligands have been employed for the stabilization of Ge(II) and Sn(II) hydrides, the corresponding Si(II) hydride is not accessible. However, coordination of silicon(II) to a {Ni(CO)(3)} fragment allowed the isolation of the first Si(II) hydride metal complex 1. This complex was used for the first silicon(II)-based and Ni(0)-mediated, stereoselective hydrosilylation of alkynes. R = phenyl, tolyl.
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Analogous to alkenes, alkynes also undergo acid-catalyzed hydration. While the addition of water to an alkene gives an alcohol, hydration of alkynes produces different products such as aldehydes and ketones.
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One of the convenient methods for the preparation of aldehydes and ketones is via hydration of alkynes. Hydroboration-oxidation of alkynes is an indirect hydration reaction in which an alkyne is treated with borane followed by oxidation with alkaline peroxide to form an enol that rapidly converts into an aldehyde or a ketone. Terminal alkynes form aldehydes, whereas internal alkynes give ketones as the final product.
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