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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?SiNIPr (NIPr = bis(2,6-diisopropylphenyl)-imidazolin-2-imino) with B(C?F?)? 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?SiNItBu (NItBu = bis(tert-butyl)-imidazolin-2-imino). Furthermore, the treatment of dimethylchlorosilane Me?(Cl)SiNIPr with AgOTf affords the contact ion pair Me?(OTf)SiNIPr by substitution of the chloride. A novel complex with the formula [Me?(DMAP)SiNIPr][OTf] was prepared by coordination with 4-dimethylamino-pyridine (DMAP). In the solid state, the DMAP adduct [Me?(DMAP)SiNIPr][OTf] contains a distinct [Me?(DMAP)SiNIPr]? moiety.

SUBMITTER: Ochiai T

PROVIDER: S-EPMC6273809 | biostudies-other | 2016 Aug

REPOSITORIES: biostudies-other

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

Ochiai Tatsumi T Szilvási Tibor T Inoue Shigeyoshi S

Molecules (Basel, Switzerland) 20160830 9

Novel silylium ions with N-heterocyclic imines were successfully synthesized. The reaction of trimethylsilyl imidazolin-2-imine Me₃SiNIPr (NIPr = bis(2,6-diisopropylphenyl)-imidazolin-2-imino) with B(C₆F₅)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 Me₃SiNItBu (NItBu = bis(tert-butyl)-imidazolin-2-imino). Furthermore, the ...[more]

PMID: 27589708

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