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Competition for Hydride Between Silicon and Boron: Synthesis and Characterization of a Hydroborane-Stabilized Silylium Ion.

ABSTRACT: Potent main-group Lewis acids are capable of activating element-hydrogen bonds. To probe the rivalry for hydride between silylium- and borenium-ion centers, a neutral precursor with the hydrosilane and hydroborane units in close proximity on a naphthalene-1,8-diyl platform was designed. Abstraction of one hydride leads to a hydroborane-stabilized silylium ion rather than a hydrosilane-coordinated borenium ion paired with [B(C₆ F₅ )₄ ]^- or [HCB₁₁ Cl₁₁ ]^- as counteranions. Characterization by multinuclear NMR spectroscopy and X-ray diffraction supported by DFT calculations reveals a cationic, unsymmetrical open three-center, two-electron (3c2e) Si-H-B linkage.

SUBMITTER: Gao H

PROVIDER: S-EPMC9303568 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Competition for Hydride Between Silicon and Boron: Synthesis and Characterization of a Hydroborane-Stabilized Silylium Ion.

Gao Haopeng H Müller Robert R Irran Elisabeth E Klare Hendrik F T HFT Kaupp Martin M Oestreich Martin M

Chemistry (Weinheim an der Bergstrasse, Germany) 20220110 12

Potent main-group Lewis acids are capable of activating element-hydrogen bonds. To probe the rivalry for hydride between silylium- and borenium-ion centers, a neutral precursor with the hydrosilane and hydroborane units in close proximity on a naphthalene-1,8-diyl platform was designed. Abstraction of one hydride leads to a hydroborane-stabilized silylium ion rather than a hydrosilane-coordinated borenium ion paired with [B(C6 F5 )4 ]- or [HCB11</ ...[more]

PMID: 34918852

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