Facile Access to Stable Silylium Ions Stabilized by N-Heterocyclic Imines

Abstract

Novel silylium ions with N-heterocyclic imines were successfully synthesized. The reaction of trimethylsilyl imidazolin-2-imine Me 3 SiNIPr (NIPr = bis(2,6-diisopropylphenyl)-imidazolin-2-imino) with B(C 6 F 5 ) 3 leads to dimeric imino-substituted silylium ions through a methyl group abstraction on the silicon atom. Meanwhile, the intermolecular imino-coordinated silylium ion is formed by using the less sterically crowded imine Me 3 SiNItBu (NItBu = bis(tert-butyl)-imidazolin-2-imino).

Three‐Coordinate Boron(III) and Diboron(II) Dications

“…The B−N bond lengths in 4 2+ amount to 1.445(5) Å and 1.447(5) Å which is shorter than the respective distances in V (1.483(5) Å and 1.493(5) Å) and suggests increased π interaction between the imino nitrogen atoms and the vacant p ‐type orbital at the boron center. Vice versa, we find elongated C−N imino bond lengths in 4 2+ (1.366(5) Å and 1.370(5) Å) which corresponds to the pronounced single‐bond character of the imino groups as generally found for NHI ligands implemented for the stabilization of cationic metal complexes ,,,. The plane of the phenyl ring and the boron‐centered trigonal plane are tilted to each other by 52° and, thus, diminished π‐interaction between these moieties is to be expected.…”

Strait Gate: Special Issue on Advances in Silicon Chemistry

“…A compilation of 12 full articles in the special issue titled “Advances in Silicon Chemistry” features currently developing areas in basic, applied, and theoretical silicon chemistry. Among them are studies of base-coordinate phosphasilenes [ 10 ], base-coordinate silyl cations [ 11 ], a new germylene [ 12 ], and σ-delocalization in structured oligosilanes [ 13 ] that encourage us to think seriously about the outlook of bonding and structure of heavy main-group elements. Hopefully, the readers will enjoy finding excellent articles in this special issue.…”